Privoxy Frequently Asked Questions
-[ Copyright © 2001-2004 by Privoxy Developers ]
+Copyright © 2001-2006 by Privoxy Developers
-$Id: faq.txt,v 1.42.2.7 2004/01/30 23:46:57 oes Exp $
+$Id: faq.sgml,v 2.19 2006/09/22 10:54:32 hal9 Exp $
-This FAQ gives quick answers to frequently asked questions about Privoxy. It
-can't and doesn't replace the User Manual.
+This FAQ gives quick answers to frequently asked questions about Privoxy. It is
+not a substitute for the Privoxy User Manual.
+
+What is Privoxy?
Privoxy is a web proxy with advanced filtering capabilities for protecting
-privacy, modifying web page content, managing cookies, controlling access, and
+privacy, modifying web page data, managing cookies, controlling access, and
removing ads, banners, pop-ups and other obnoxious Internet junk. Privoxy has a
very flexible configuration and can be customized to suit individual needs and
tastes. Privoxy has application for both stand-alone systems and multi-user
Privoxy is based on Internet Junkbuster (tm).
-Please note that this document is constantly evolving. This copy represents the
-state at the release of version 3.0.3. You can find the latest version of the
+Please note that this document is a work in progress. This copy represents the
+state at the release of version 3.0.5. You can find the latest version of the
document at http://www.privoxy.org/faq/. Please see the Contact section if you
want to contact the developers.
Table of Contents
1. General Information
-
- 1.1. What is this new version of Privoxy?
- 1.2. Why "Privoxy"? Why a name change at all?
- 1.3. How does Privoxy differ from the old Junkbuster?
- 1.4. What is a "proxy"? How does Privoxy work?
- 1.5. How does Privoxy know what is an ad, and what is not?
- 1.6. Can Privoxy make mistakes? This does not sound very scientific.
- 1.7. Will I have to configure Privoxy before I can use it?
- 1.8. My browser does the same things as Privoxy. Why should I use Privoxy
+
+ 1.1. Who should use Privoxy?
+ 1.2. Is Privoxy the best choice for me?
+ 1.3. What is a "proxy"? How does Privoxy work?
+ 1.4. What is this new version of "Junkbuster"?
+ 1.5. Why "Privoxy"? Why change the name from Junkbuster at all?
+ 1.6. How does Privoxy differ from the old Junkbuster?
+ 1.7. How does Privoxy know what is an ad, and what is not?
+ 1.8. Can Privoxy make mistakes? This does not sound very scientific.
+ 1.9. Will I have to configure Privoxy before I can use it?
+ 1.10. My browser does the same things as Privoxy. Why should I use Privoxy
at all?
- 1.9. Is there is a license or fee? What about a warranty? Registration?
- 1.10. I would like to help you, what do I do?
-
- 1.10.1. Money Money Money
- 1.10.2. Software
- 1.10.3. You want to work with us?
-
+ 1.11. Why should I trust Privoxy?
+ 1.12. Is there is a license or fee? What about a warranty? Registration?
+ 1.13. Can Privoxy remove spyware? Adware? Viruses?
+ 1.14. Can I use Privoxy with other ad-blocking software?
+ 1.15. I would like to help you, what can I do?
+
+ 1.15.1. Would you like to participate?
+ 1.15.2. Contribute!
+ 1.15.3. Software
+
2. Installation
-
+
2.1. Which browsers are supported by Privoxy?
2.2. Which operating systems are supported?
2.3. Can I use Privoxy with my email client?
there. What's wrong?
2.8. I get a "Privoxy is not being used" dummy page although Privoxy is
running and being used.
-
+
3. Configuration
-
+
3.1. Where can I get updated Actions Files?
3.2. Can I use my old config files?
- 3.3. What is an "actions" file?
+ 3.3. What exactly is an "actions" file?
3.4. The "actions" concept confuses me. Please list some of these
"actions".
3.5. How are actions files configured? What is the easiest way to do this?
3.6. There are several different "actions" files. What are the differences?
- 3.7. How can I make my Yahoo/Hotmail/GMX account work?
- 3.8. What's the difference between the "Cautious", "Medium" and
- "Adventuresome" defaults?
+ 3.7. How can I make my Yahoo/Hotmail/Gmail account work?
+ 3.8. What's the difference between the "Cautious", "Medium" and "Advanced"
+ defaults?
3.9. Why can I change the configuration with a browser? Does that not raise
security issues?
3.10. What is the default.filter file? What is a "filter"?
3.13. Why would anybody want to see a checkerboard pattern?
3.14. I see some images being replaced by a text instead of the
checkerboard image. Why and how do I get rid of this?
- 3.15. Can Privoxy run as a service on Win2K/NT?
- 3.16. How can I make Privoxy work with other proxies like Squid?
+ 3.15. Can Privoxy run as a service on Win2K/NT/XP?
+ 3.16. How can I make Privoxy work with other proxies like Squid or Tor?
3.17. Can I just set Privoxy to use port 80 and thus avoid individual
browser configuration?
3.18. Can Privoxy run as a "transparent" proxy?
3.19. How can I configure Privoxy for use with Outlook Express?
3.20. How can I have separate rules just for HTML mail?
- 3.21. How can I allow permanent cookies for my trusted sites?
-
+ 3.21. I sometimes notice cookies sneaking through. How?
+ 3.22. Are all cookies bad? Why?
+ 3.23. How can I allow permanent cookies for my trusted sites?
+ 3.24. Can I have separate configurations for different users?
+ 3.25. Can I set-up Privoxy as a whitelist of "good" sites?
+
4. Miscellaneous
-
+
4.1. How much does Privoxy slow my browsing down? This has to add extra
time to browsing.
- 4.2. I noticed considerable delays in page requests compared to the old
+ 4.2. I notice considerable delays in page requests compared to the old
Junkbuster. What's wrong?
4.3. What are "http://config.privoxy.org/" and "http://p.p/"?
- 4.4. Do you still maintain the blocklists?
- 4.5. How can I submit new ads?
+ 4.4. How can I submit new ads, or report problems?
+ 4.5. Why doesn't anyone answer my support request?
4.6. How can I hide my IP address?
4.7. Can Privoxy guarantee I am anonymous?
- 4.8. Might some things break because header information or content is being
- altered?
- 4.9. Can Privoxy act as a "caching" proxy to speed up web browsing?
- 4.10. What about as a firewall? Can Privoxy protect me?
- 4.11. I have large empty spaces / a checkerboard pattern now where ads used
+ 4.8. A test site says I am not using a Proxy.
+ 4.9. How do I use Privoxy together with Tor?
+ 4.10. Might some things break because header information or content is
+ being altered?
+ 4.11. Can Privoxy act as a "caching" proxy to speed up web browsing?
+ 4.12. What about as a firewall? Can Privoxy protect me?
+ 4.13. I have large empty spaces / a checkerboard pattern now where ads used
to be. Why?
- 4.12. How can Privoxy filter Secure (HTTPS) URLs?
- 4.13. Privoxy runs as a "server". How secure is it? Do I need to take any
+ 4.14. How can Privoxy filter Secure (HTTPS) URLs?
+ 4.15. Privoxy runs as a "server". How secure is it? Do I need to take any
special precautions?
- 4.14. How can I temporarily disable Privoxy?
- 4.15. When "disabled" is Privoxy totally out of the picture?
- 4.16. My logs show Privoxy "crunches" ads, but also its own CGI pages. What
- is a "crunch"?
- 4.17. Can Privoxy effect files that I download from a webserver? FTP
+ 4.16. How can I temporarily disable Privoxy?
+ 4.17. When "disabled" is Privoxy totally out of the picture?
+ 4.18. My logs show Privoxy "crunches" ads, but also its own internal CGI
+ pages. What is a "crunch"?
+ 4.19. Can Privoxy effect files that I download from a webserver? FTP
server?
- 4.18. I just downloaded a Perl script, and Privoxy altered it! Yikes, what
+ 4.20. I just downloaded a Perl script, and Privoxy altered it! Yikes, what
is wrong!
- 4.19. Where can I find more information about Privoxy and related issues?
- 4.20. I've noticed that Privoxy changes "Microsoft" to "MicroSuck"! Why are
+ 4.21. Should I continue to use a "HOSTS" file for ad-blocking?
+ 4.22. Where can I find more information about Privoxy and related issues?
+ 4.23. I've noticed that Privoxy changes "Microsoft" to "MicroSuck"! Why are
you manipulating my browsing?
-
+
5. Troubleshooting
-
- 5.1. I just upgraded and am getting "connection refused" with every web
- page?
+
+ 5.1. I am getting "connection refused" with every web page?
5.2. I just added a new rule, but the steenkin ad is still getting through.
How?
5.3. One of my favorite sites does not work with Privoxy. What can I do?
5.4. After installing Privoxy, I have to log in every time I start IE. What
gives?
- 5.5. I cannot connect to any FTP sites. Privoxy seems to be blocking me.
+ 5.5. I cannot connect to any FTP sites. Privoxy is blocking me.
5.6. In Mac OSX, I can't configure Microsoft Internet Explorer to use
Privoxy as the HTTP proxy.
5.7. In Mac OSX, I dragged the Privoxy folder to the trash in order to
5.14. Why are binary files (such as images) corrupted when Privoxy is used?
5.15. What is the "demoronizer" and why is it there?
5.16. Why do I keep seeing "PrivoxyWindowOpen()" in raw source code?
-
+ 5.17. I am getting too many DNS errors like "404 No Such Domain". Why can't
+ Privoxy do this better?
+ 5.18. At one site Privoxy just hangs, and starts taking all CPU. Why is
+ this?
+ 5.19. I just installed Privoxy, and all my browsing has slowed to a crawl.
+ What gives?
+
6. Contacting the developers, Bug Reporting and Feature Requests
-
+
6.1. Get Support
- 6.2. Report Bugs
+ 6.2. Reporting Problems
+
+ 6.2.1. Reporting Ads or Other Configuration Problems
+ 6.2.2. Reporting Bugs
+
6.3. Request New Features
- 6.4. Report Ads or Other Actions-Related Problems
- 6.5. Other
-
+ 6.4. Other
+
7. Privoxy Copyright, License and History
-
+
7.1. License
7.2. History
-
+
1. General Information
-1.1. What is this new version of Privoxy?
+1.1. Who should use Privoxy?
+
+Anyone that is interested in security, privacy, or in finer-grained control
+over their web and Internet experience. Everyone is encouraged to try Privoxy.
+
+-------------------------------------------------------------------------------
+
+1.2. Is Privoxy the best choice for me?
+
+Privoxy is certainly a good choice, especially for those who want more control
+and security. Those that have the ability to fine-tune their installation will
+benefit the most. One of Privoxy's strength's is that it is highly configurable
+giving you the ability to completely personalize your installation. Being
+familiar with, or at least having an interest in learning about HTTP and other
+networking protocols, HTML, IP (Internet Protocol), and "Regular Expressions"
+will be a big plus and will help you get the most out of Privoxy.
+
+Much of Privoxy's configuration can be done with a Web browser. But there are
+areas where configuration is done using a text editor to edit configuration
+files.
+
+-------------------------------------------------------------------------------
+
+1.3. What is a "proxy"? How does Privoxy work?
+
+A web proxy is a service, based on a software such as Privoxy, that clients
+(i.e. browsers) can use instead of connecting directly to web servers on the
+Internet. The clients then ask the proxy to fetch the objects they need (web
+pages, images, movies etc) on their behalf, and when the proxy has done so, it
+hands the results back to the client. It is a "go-between". See the Wikipedia
+proxy definition for more.
+
+There are many reasons to use web proxies, such as security (firewalling),
+efficiency (caching) and others, and there are any number of proxies to
+accommodate those needs.
-In the beginning, there was the Internet Junkbuster, by Anonymous Coders and
-Junkbusters Corporation. It saved many users a lot of pain in the early days of
-web advertising and user tracking.
+Privoxy is a proxy that is primarily focused on privacy protection, ad and junk
+elimination and freeing the user from restrictions placed on his activities.
+Sitting between your browser(s) and the Internet, it is in a perfect position
+to filter outbound personal information that your browser is leaking, as well
+as inbound junk. It uses a variety of techniques to do this, all of which are
+under your complete control via the various configuration files and options.
+
+-------------------------------------------------------------------------------
+
+1.4. What is this new version of "Junkbuster"?
+
+Along time ago, there was the Internet Junkbuster, by Anonymous Coders and
+Junkbusters Corporation. This saved many users a lot of pain in the early days
+of web advertising and user tracking.
But the web, its protocols and standards, and with it, the techniques for
-forcing users to consume ads, give up autonomy over their browsing, and for
-spying on them, kept evolving. Unfortunately, the Internet Junkbuster did not.
-Version 2.0.2, published in 1998, was (and is) the last official release
-available from Junkbusters Corporation. Fortunately, it had been released under
-the GNU GPL, which allowed further development by others.
+forcing ads on users, give up autonomy over their browsing, and for tracking
+them, keeps evolving. Unfortunately, the Internet Junkbuster did not. Version
+2.0.2, published in 1998, was (and is) the last official release available from
+Junkbusters Corporation. Fortunately, it had been released under the GNU GPL,
+which allowed further development by others.
So Stefan Waldherr started maintaining an improved version of the software, to
which eventually a number of people contributed patches. It could already
-------------------------------------------------------------------------------
-1.2. Why "Privoxy"? Why a name change at all?
-
-Privoxy is the "Privacy Enhancing Proxy". Also, its content modification and
-junk suppression allow you to browse your "private edition" of the web.
+1.5. Why "Privoxy"? Why change the name from Junkbuster at all?
Junkbusters Corporation continues to offer their original version of the
Internet Junkbuster, so publishing our Junkbuster-derived software under the
There are, however, no objections from Junkbusters Corporation to the Privoxy
project itself, and they, in fact, still share our ideals and goals.
-The developers also believed that there are so many changes from the original
-code, that it was time to make a clean break from the past and make a name in
-their own right.
+The developers also believed that there are so many improvements over the
+original code, that it was time to make a clean break from the past and make a
+name in their own right.
+
+Privoxy is the "Privacy Enhancing Proxy". Also, its content modification and
+junk suppression gives you, the user, more control, more freedom, and allows
+you to browse your personal and "private edition" of the web.
-------------------------------------------------------------------------------
-1.3. How does Privoxy differ from the old Junkbuster?
+1.6. How does Privoxy differ from the old Junkbuster?
Privoxy picks up where Junkbuster left off. All the old features remain. The
new Privoxy still blocks ads and banners, still manages cookies, and still
-helps protect your privacy. But, these are all enhanced, and many new features
-have been added, all in the same vein.
+helps protect your privacy. But, these are all greatly enhanced, and many, many
+new features have been added, all in the same vein.
The configuration has changed significantly as well. This is something that
users will notice right off the bat if upgrading from Junkbuster 2.0.x. The
"blocklist" "cookielist", "imagelist" and much more has been combined into the
-"actions" files, with a completely different syntax. See the note to upgraders
-for details.
+"actions" files, with a completely different syntax. See the What's New page
+for the latest updates.
Privoxy's new features include:
* Integrated browser based configuration and control utility at http://
config.privoxy.org/ (shortcut: http://p.p/). Browser-based tracing of rule
and filter effects. Remote toggling.
-
+
* Web page content filtering (removes banners based on size, invisible
"web-bugs", JavaScript and HTML annoyances, pop-up windows, etc.)
-
+
* Modularized configuration that allows for standard settings and user
settings to reside in separate files, so that installing updated actions
files won't overwrite individual user settings.
-
+
* HTTP/1.1 compliant (but not all optional 1.1 features are supported).
-
+
* Support for Perl Compatible Regular Expressions in the configuration files,
and generally a more sophisticated and flexible configuration syntax over
previous versions.
-
+
* Improved cookie management features (e.g. session based cookies).
-
+
* GIF de-animation.
-
+
* Bypass many click-tracking scripts (avoids script redirection).
-
+
* Multi-threaded (POSIX and native threads).
-
+
* User-customizable HTML templates for all proxy-generated pages (e.g.
"blocked" page).
-
+
* Auto-detection and re-reading of config file changes.
-
+
* Improved signal handling, and a true daemon mode (Unix).
-
+
* Every feature now controllable on a per-site or per-location basis,
configuration more powerful and versatile over-all.
-
+
* Many smaller new features added, limitations and bugs removed, and security
holes fixed.
-
+
-------------------------------------------------------------------------------
-1.4. What is a "proxy"? How does Privoxy work?
-
-A web proxy is a service, based on a software such as Privoxy, that clients
-(i.e. browsers) can use instead of connecting directly to the web servers on
-the Internet. The clients then ask the proxy to fetch the objects they need
-(web pages, images, movies etc) on their behalf, and when the proxy has done
-so, it hands the results back to the client.
-
-There are many reasons to use web proxies, such as security (firewalling),
-efficiency (caching) and others, and there are just as many different proxies
-to accommodate those needs.
-
-Privoxy is a proxy that is solely focused on privacy protection and junk
-elimination. Sitting between your browser(s) and the Internet, it is in a
-perfect position to filter outbound personal information that your browser is
-leaking, as well as inbound junk. It uses a variety of techniques to do this,
-all of which are under your control via the various configuration files and
-options.
-
--------------------------------------------------------------------------------
-
-1.5. How does Privoxy know what is an ad, and what is not?
+1.7. How does Privoxy know what is an ad, and what is not?
Privoxy's approach to blocking ads is twofold:
their banners from a directory called "banners"!) and the host (blocking the
big banner hosting services like doublecklick.net already helps a lot). Privoxy
takes advantage of this fact by using URL patterns to sort out and block the
-requests for banners.
+requests for things that sound like they would be ads or banners.
Second, banners tend to come in certain sizes. But you can't tell the size of
an image by its URL without downloading it, and if you do, it's too late to
the first place.
Both of this involves a certain amount of guesswork and is, of course, freely
-configurable.
+and readily configurable.
-------------------------------------------------------------------------------
-1.6. Can Privoxy make mistakes? This does not sound very scientific.
+1.8. Can Privoxy make mistakes? This does not sound very scientific.
Actually, it's a black art ;-) And yes, it is always possible to have a broad
rule accidentally block or change something by mistake. You will almost surely
-------------------------------------------------------------------------------
-1.7. Will I have to configure Privoxy before I can use it?
+1.9. Will I have to configure Privoxy before I can use it?
No, not really. The default installation should give you a good starting point,
and block most unwanted content.
your individual situation. And we would encourage you to do this. This is where
the real power of Privoxy lies!
+You will have to tell your browser about Privoxy (see the Installation section
+below).
+
-------------------------------------------------------------------------------
-1.8. My browser does the same things as Privoxy. Why should I use Privoxy at
+1.10. My browser does the same things as Privoxy. Why should I use Privoxy at
all?
Modern browsers do indeed have some of the same functionality as Privoxy. Maybe
-------------------------------------------------------------------------------
-1.9. Is there is a license or fee? What about a warranty? Registration?
+1.11. Why should I trust Privoxy?
+
+The most important reason is because you have access to everything, and you can
+control everything. You can check every line of every configuration file
+yourself. You can check every last bit of source code should you desire. And
+even if you can't read code, there should be some comfort in knowing that
+thousands of other people can, and do read it. You can build the software from
+scratch, if you want, so that you know the executable is clean, and that it is
+yours. In fact, we encourage this level of scrutiny. It is one reason we use
+Privoxy ourselves.
+
+-------------------------------------------------------------------------------
+
+1.12. Is there is a license or fee? What about a warranty? Registration?
Privoxy is licensed under the GNU General Public License (GPL). It is free to
use, copy, modify or distribute as you wish under the terms of this license.
-------------------------------------------------------------------------------
-1.10. I would like to help you, what do I do?
+1.13. Can Privoxy remove spyware? Adware? Viruses?
+
+No. Privoxy cannot remove anything. It is not a removal tool. It is a
+preventative. Privoxy can help prevent contact from sites that use such tactics
+with approriate configuration rules, and thus could conceivably prevent
+contamination from such sites.
+
+-------------------------------------------------------------------------------
+
+1.14. Can I use Privoxy with other ad-blocking software?
+
+Privoxy should work fine with other proxies and other software in general.
-1.10.1. Money Money Money
+But it is probably not necessary to use Privoxy in conjunction with other
+ad-blocking products, and this could conceivably cause undesirable results. It
+would be better to choose one software or the other and work a little to tweak
+its configuration to your liking.
+
+-------------------------------------------------------------------------------
+
+1.15. I would like to help you, what can I do?
+
+1.15.1. Would you like to participate?
+
+Well, we always need help. There is something for everybody who wants to help
+us. We welcome new developers, packagers, testers, documentation writers or
+really anyone with a desire to help in any way. You DO NOT need to be a
+"programmer". There are many other tasks available. In fact, the programmers
+often can't spend as much time programming because of some of the other, more
+mundane things that need to be done, like checking the Tracker feedback
+sections.
+
+So first thing, get an account on SourceForge.net and mail your id to the
+developers mailing list. Then, please read the Developer's Manual, at least the
+pertinent sections.
+
+Once we have added you to the team, you'll have access to the CVS repository,
+and together we'll find a suitable task for you.
+
+-------------------------------------------------------------------------------
+
+1.15.2. Contribute!
We, of course, welcome donations and could use money for domain registering,
buying software to test Privoxy with, and, of course, for regular world-wide
-------------------------------------------------------------------------------
-1.10.2. Software
+1.15.3. Software
If you are a vendor of a web-related software like a browser, web server or
proxy, and would like us to ensure that Privoxy runs smoothly with your
-------------------------------------------------------------------------------
-1.10.3. You want to work with us?
-
-Well, helping the team is always a good idea. We welcome new developers,
-packaging gurus or documentation writers. Simply get an account on
-SourceForge.net and mail your id to the developers mailing list. Then read the
-Developer's Manual.
-
-Once we have added you to the team, you'll have write access to the CVS
-repository, and together we'll find a suitable task for you.
-
--------------------------------------------------------------------------------
-
2. Installation
2.1. Which browsers are supported by Privoxy?
Any browser that can be configured to use a proxy, which should be virtually
-all browsers. Direct browser support is not necessary since Privoxy runs as a
+all browsers, including Firefox, Internet Explorer, and Opera among others.
+Direct browser support is not an absolute requirement since Privoxy runs as a
separate application and talks to the browser in the standardized HTTP
protocol, just like a web server does.
2.2. Which operating systems are supported?
At present, Privoxy is known to run on Windows(95, 98, ME, 2000, XP), Linux
-(RedHat, SuSE, Debian, Conectiva, Gentoo, Slackware), Mac OSX, OS/2, AmigaOS,
-BeOS, FreeBSD, NetBSD, OpenBSD, Solaris, and many more flavors of Unix.
+(RedHat, SuSE, Debian, Fedora, Gentoo, Slackware and others), Mac OSX, OS/2,
+AmigaOS, FreeBSD, NetBSD, OpenBSD, Solaris, and various other flavors of Unix.
But any operating system that runs TCP/IP, can conceivably take advantage of
Privoxy in a networked situation where Privoxy would run as a server on a LAN
confusion. You may want to save your old configuration files for future
reference. The configuration files and syntax have substantially changed, so
you will need to manually port your old patterns. See the note to upgraders and
-installation chapter in the user manual for details.
+installation chapter in the User Manual for details.
Note: Some installers may automatically un-install Junkbuster, if present!
All browsers must be told to use Privoxy as a proxy by specifying the correct
proxy address and port number in the appropriate configuration area for the
browser. See below. You should also flush your browser's memory and disk cache
-to get rid of any cached junk items, and remove any stored cookies.
+to get rid of any cached junk items, and remove any stored cookies.
-------------------------------------------------------------------------------
Privoxy doesn't listen on any LAN interfaces by default.
Privoxy does not currently handle any other protocols such as FTP, SMTP, IM,
-IRC, ICQ, etc.
+IRC, ICQ, etc. Be sure that proxying any of these other protocols is not
+activated.
-------------------------------------------------------------------------------
nothing at all), it could either be that the browser is not set up correctly,
or that Privoxy is not running at all. Check the log file. For instructions on
starting Privoxy and browser configuration, see the chapter on starting Privoxy
-in the user manual.
+in the User Manual.
-------------------------------------------------------------------------------
2.8. I get a "Privoxy is not being used" dummy page although Privoxy is running
and being used.
-First, make sure that Privoxy is really running and being used by visiting
+First, make sure that Privoxy is really running and being used by visiting
http://p.p/. You should see the Privoxy main page. If not, see the chapter on
-starting Privoxy in the user manual.
+starting Privoxy in the User Manual.
Now if http://p.p/ works for you, but other parts of Privoxy's web interface
show the dummy page, your browser has cached a redirection it encountered
that shift-reloading the dummy page won't help, since that'll only refresh the
dummy page, not the redirection that lead you there.
-The procedure for clearing the cache varies from browser to browser. As an
-example, Mozilla users would click Edit --> Preferences --> Advanced --> Cache
-and then click both "Clear Memory Cache" and "Clear Disk Cache".
+The procedure for clearing the cache varies from browser to browser. For
+example, Mozilla/Netscape users would click Edit --> Preferences --> Advanced
+--> Cache and then click both "Clear Memory Cache" and "Clear Disk Cache". And,
+Firefox users would click Tools --> Options --> Privacy --> Cache and then
+click "Clear Cache Now".
-------------------------------------------------------------------------------
3.1. Where can I get updated Actions Files?
-Based on your feedback and the continuing development, updated actions files
-will be made available on the files section of our project page.
+Based on your feedback and the continuing development, updates of
+default.action will be made available from time to time on the files section of
+our project page.
If you wish to receive an email notification whenever we release updates of
Privoxy or the actions file, subscribe to our announce mailing list,
3.2. Can I use my old config files?
-The syntax, number, and purpose of configuration files has substantially
-changed from Junkbuster and earlier versions of Privoxy. The old files, like
-blocklist will not work at all. If you are upgrading from a 2.0.x version, you
-will need to port your configuration data to the new format. Note that even the
-pattern syntax has changed! Even configuration files from the 2.9.x versions
-will need to be adapted, as configuration syntax has been very much in flow in
-the 2.9.x series.
+The syntax and purpose of configuration files has remained the same throughout
+the 3.x series. Although each release contains updated, "improved" versions and
+it is recommended to use the newer configuration files. If upgrading from
+version prior to 3.0.4 the syntax for fast-redirects has changed. See the
+What's New section of the User Manual for details.
+
+But all configuration files have substantially changed from the Junkbuster
+days, and early versions of Privoxy 2.x. The old files, like blocklist will not
+work at all.
+
+Refer to the What's New page for information on configuration changes that may
+occur from one release to another.
-------------------------------------------------------------------------------
-3.3. What is an "actions" file?
+3.3. What exactly is an "actions" file?
-Actions files are where various actions that Privoxy might take while
+Actions files are where various actions that Privoxy could take while
processing a certain request, are configured. Typically, you would define a set
of default actions that apply to all URLs, then add exceptions to these
-defaults where needed.
+defaults where needed. There is a wide array of actions available that give the
+user a high degree of control and flexibility on how to process each and every
+web page.
Actions can be defined on a URL pattern basis, i.e. for single URLs, whole web
sites, groups or parts thereof etc. Actions can also be grouped together and
then applied to requests matching one or more patterns. There are many possible
-actions that might apply to any given site. As an example, if you are blocking
+actions that might apply to any given site. As an example, if you are blocking
cookies as one of your default actions, but need to accept cookies from a given
site, you would need to define an exception for this site in one of your
actions files, preferably in user.action.
3.4. The "actions" concept confuses me. Please list some of these "actions".
-For a comprehensive discussion of the actions concept, please refer to the
+For a comprehensive discussion of the actions concept, please refer to the
actions file chapter in the user manual. It includes a list of all actions and
an actions file tutorial to get you started.
different purposes: These are default.action, the "main" actions file which is
actively maintained by the Privoxy developers, user.action, where users are
encouraged to make their private customizations, and standard.action, which is
-for internal Privoxy use only. Please see the actions chapter in the user
-manual for a more detailed explanation.
+for internal Privoxy use only. Please see the actions chapter in the User
+Manual for a more detailed explanation.
Earlier versions included three different versions of the default.action file.
The new scheme allows for greater flexibility of local configuration, and for
-------------------------------------------------------------------------------
-3.7. How can I make my Yahoo/Hotmail/GMX account work?
+3.7. How can I make my Yahoo/Hotmail/Gmail account work?
The default configuration shouldn't impact the usability of any of these
services. It will, however, make all cookies temporary, so that your browser
turn off all cookie handling for them in the user.action file. An example for
yahoo might look like:
-# Allow all cookies for Yahoo login:
-#
-{ -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only }
-.login.yahoo.com
+# Allow all cookies for Yahoo login:
+#
+{ -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only }
+.login.yahoo.com
+These kinds of sites are often quite complex and heavy with Javascript and thus
+"fragile". So if still a problem, we have an alias just for such sticky
+situations:
+
+# Gmail is a _fragile_ site:
+#
+{ fragile }
+ mail.google.com
+
+Be sure to flush your browser's caches whenever making these kinds of changes,
+just to make sure the changes "take".
+
+Make sure the domain, host and path are appropriate as well. Your browser can
+tell you where you are specifically and you should use that information for
+your configuration settings. Note that above it is not referenced as gmail.com,
+which is a valid domain name.
-------------------------------------------------------------------------------
-3.8. What's the difference between the "Cautious", "Medium" and "Adventuresome"
+3.8. What's the difference between the "Cautious", "Medium" and "Advanced"
defaults?
Configuring Privoxy is not entirely trivial. To help you get started, we
Where the defaults are likely to break some sites, exceptions for known popular
"problem" sites are included, but in general, the more aggressive your default
settings are, the more exceptions you will have to make later. See the User
-Manual for a more deatiled discussion.
+Manual for a more detailed discussion.
-It should be noted that the "Adventuresome" profile (formerly known as the
-"Advanced" profile) is not only more aggressive, but also includes fun and,
-extreme usage of most of Privoxy's features. Use at your own risk!
+It should be noted that the "Advanced" profile (formerly known as the
+"Adventuresome" profile) is more aggressive, and will make use of some of
+Privoxy's advanced features. Use at your own risk!
-------------------------------------------------------------------------------
3.10. What is the default.filter file? What is a "filter"?
-The default.filter file is where filters are defined, which can be used to
-modify or remove, web page content on the fly. Filters apply to anything in the
-page source, including HTML tags, and JavaScript. Regular expressions are used
-to accomplish this. There are a number of pre-defined filters to deal with
-common annoyances. The filters are only defined here, to invoke them, you need
-to use the filter action in one of the actions files. Filtering is
-automatically disabled for inappropriate MIME types.
+The default.filter file is where filters as supplied by the developers are
+defined. Filters are a special subset of actions that can be used to modify or
+remove, web page content on the fly. Filters apply to anything in the page
+source (and optionally both client and server headers), including HTML tags,
+and JavaScript. Regular expressions are used to accomplish this. There are a
+number of pre-defined filters to deal with common annoyances. The filters are
+only defined here, to invoke them, you need to use the filter action in one of
+the actions files. Filtering is automatically disabled for inappropriate MIME
+types.
If you are familiar with regular expressions, and HTML, you can look at the
provided default.filter with a text editor and define your own filters. This is
potentially a very powerful feature, but requires some expertise in both
-regular expressions and HTML/HTTP.
+regular expressions and HTML/HTTP. You should place any modifications to the
+default filters, or any new ones you create in a separate file, such as
+user.filter, so they won't be overwritten during upgrades. The ability to
+define multiple filter files in config is a new feature as of v. 3.0.5.
-Presently, there is no GUI editor option for this part of the configuration,
-but you can disable/enable the various pre-defined filters of the included
-default.filter file with the web-based actions file editor.
+There is no GUI editor option for this part of the configuration, but you can
+disable/enable the various pre-defined filters of the included default.filter
+file with the web-based actions file editor.
-------------------------------------------------------------------------------
is 192.168.1.1 and you wish to run Privoxy on port 8118, this line should look
like:
- listen-address 192.168.1.1:8118
-
+ listen-address 192.168.1.1:8118
Save the file, and restart Privoxy. Configure all browsers on the network then
to use this address and port number.
Alternately, you can have Privoxy listen on all available interfaces:
- listen-address :8118
-
+ listen-address :8118
And then use Privoxy's permit-access feature to limit connections. A firewall
in this situation is recommended as well.
URLs match both a handle-as-image and block action.
If you want to see nothing, then change the set-image-blocker action to
-"blank". This can be done by editing the default.action file, or trough the
+"blank". This can be done by editing the default.action file, or trough the
web-based actions file editor.
-------------------------------------------------------------------------------
guesswork. While we hope that the standard configuration is rather smart, it
can and will make errors. The checkerboard image is visually decent, but it
shows you that and where images were blocked, which can be very helpful in case
-some navigation aid or otherwise innocent image was erraneously blocked. Some
+some navigation aid or otherwise innocent image was erroneously blocked. Some
people might also enjoy seeing how many banners they don't have to see..
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
-3.15. Can Privoxy run as a service on Win2K/NT?
+3.15. Can Privoxy run as a service on Win2K/NT/XP?
-Yes, it can run as a system service using srvany.exe. See the discussion at
-http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=
-11118, for details, and a sample configuration.
+Yes. Version 3.0.5 introduces full Windows service functionality. See the User
+Manual for details on how to install and configure Privoxy as a service.
-Version 3.0.1 fixes the problem where the icon and menu where not available in
-the taskbar for this usage.
+Earlier 3.x versions could run as a system service using srvany.exe. See the
+discussion at http://sourceforge.net/tracker/?func=detail&atid=361118&aid=
+485617&group_id=11118, for details, and a sample configuration.
-------------------------------------------------------------------------------
-3.16. How can I make Privoxy work with other proxies like Squid?
+3.16. How can I make Privoxy work with other proxies like Squid or Tor?
This can be done and is often useful to combine the benefits of Privoxy with
-those of a caching proxy. See the forwarding chapter in the user manual which
-describes how to do this.
+those of a another proxy. See the forwarding chapter in the User Manual which
+describes how to do this, and the How do I use Privoxy together with Tor
+section below.
-------------------------------------------------------------------------------
3.18. Can Privoxy run as a "transparent" proxy?
-No, Privoxy currently does not have this ability, though it is planned for a
+No, Privoxy currently does not have this ability, though it may be added in a
future release. Transparent proxies require special handling of the request
headers beyond what Privoxy is now capable of.
Chaining Privoxy behind another proxy that has this ability should work though.
-See the forwarding chapter in the user manual. As a transparent proxy to be
-used for chaining we recommend Transproxy (http://www.transproxy.nlc.net.au/).
+See the forwarding chapter in the User Manual. As a transparent proxy to be
+used for chaining we recommend Transproxy (http://transproxy.sourceforge.net/).
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
-3.21. How can I allow permanent cookies for my trusted sites?
+3.21. I sometimes notice cookies sneaking through. How?
+
+Cookies can be set in several ways. The classic method is via the Set-Cookie
+HTTP header. This is straightforward, and an easy one to manipulate, such as
+the Privoxy concept of session-cookies-only. There is also the possibility of
+using Javascript to set cookies (Privoxy calls these content-cookies). This is
+trickier because the syntax can vary widely, and thus requires a certain amount
+of guesswork. It is not realistic to catch all of these short of disabling
+Javascript, which would break many sites. And lastly, if the cookies are
+embedded in a HTTPS/SSL secure session via Javascript, they are beyond
+Privoxy's reach.
+
+All in all, Privoxy can help manage cookies in general, can help minimize the
+loss of privacy posed by cookies, but can't realistically stop all cookies.
+
+-------------------------------------------------------------------------------
+
+3.22. Are all cookies bad? Why?
+
+No, in fact there are many beneficial uses of cookies. Cookies are just a
+method that browsers can use to store data between pages, or between browser
+sessions. Sometimes there is a good reason for this, and the user's life is a
+bit easier as a result. But there is a long history of some websites taking
+advantage of this layer of trust, and using the data they glean from you and
+your browsing habits for their own purposes, and maybe to your potential
+detriment. Such sites are using you and storing their data on your system. That
+is why the security conscious watch from whom those cookies come, and why they
+really need to be there.
+
+See the Wikipedia cookie definition for more.
+
+-------------------------------------------------------------------------------
+
+3.23. How can I allow permanent cookies for my trusted sites?
There are several actions that relate to cookies. The default behavior is to
allow only "session cookies", which means the cookies only last for the current
To disable all cookie actions, so that cookies are allowed unrestricted, both
in and out, for example.com:
- { -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only -filter{content-cookies} }
- .example.com
-
+ { -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only -filter{content-cookies} }
+ .example.com
Place the above in user.action. Note some of these may be off by default
anyway, so this might be redundant, but there is no harm being explicit in what
you want to happen. user.action includes an alias for this situation, called
-allow-cookies.
+allow-all-cookies.
+
+-------------------------------------------------------------------------------
+
+3.24. Can I have separate configurations for different users?
+
+Each instance of Privoxy has its own configuration, including such attributes
+as the TCP port that it listens on. What you can do is run multiple instances
+of Privoxy, each with a unique listen-address and configuration path, and then
+each of these can have their own configurations. Think of it as per-port
+configuration.
+
+Simple enough for a few users, but for large installations, consider having
+groups of users that might share like configurations.
+
+-------------------------------------------------------------------------------
+
+3.25. Can I set-up Privoxy as a whitelist of "good" sites?
+
+Sure. There are a couple of things you can do for simple whitelisting. Here's
+one real easy one:
+
+ ############################################################
+ # Blacklist
+ ############################################################
+ { +block }
+ / # Block *all* URLs
+
+ ############################################################
+ # Whitelist
+ ############################################################
+ { -block }
+ kids.example.com
+ toys.example.com
+ games.example.com
+
+This allows access to only those three sites.
+
+A more interesting approach is Privoxy's trustfile concept, which incorporates
+the notion of "trusted referrers". See the User Manual Trust documentation.
+
+These are fairly simple approaches and are not completely foolproof. There are
+various other configuration options that should be disabled (described
+elsewhere here and in the User Manual) so that users can't modify their own
+configuration and easily circumvent the whitelist.
-------------------------------------------------------------------------------
4.1. How much does Privoxy slow my browsing down? This has to add extra time to
browsing.
-It should not slow you down any in real terms, and may actually help speed
-things up since ads, banners and other junk are not being displayed. The actual
-processing time required by Privoxy itself for each page, is relatively small
-in the overall scheme of things, and happens very quickly. This is typically
-more than offset by time saved not downloading and rendering ad images.
+How much of an impact depends on many things, including the CPU of the host
+system, how aggressive the configuration is, which specific actions are being
+triggered, the size of the page, etc.
+
+Overall, it should not slow you down any in real terms, and may actually help
+speed things up since ads, banners and other junk are not typically being
+retrieved and displayed. The actual processing time required by Privoxy itself
+for each page, is relatively small in the overall scheme of things, and happens
+very quickly. This is typically more than offset by time saved not downloading
+and rendering ad images (if ad blocking is being used).
-"Filtering" content via the filter or deanimate-gifs actions may cause a
-perceived slowdown, since the entire document needs to be buffered before
-displaying. See below.
+"Filtering" content via the filter or deanimate-gifs actions will certainly
+cause a perceived slowdown, since the entire document needs to be buffered
+before displaying. And on very large documents, there may be some impact. How
+much depends on the page size, the actual definition of the filter(s), etc. See
+below. Most other actions have little to no impact on speed.
-------------------------------------------------------------------------------
-4.2. I noticed considerable delays in page requests compared to the old
+4.2. I notice considerable delays in page requests compared to the old
Junkbuster. What's wrong?
If you use any filter action, such as filtering banners by size, web-bugs etc,
order for the filtering mechanism to work, and nothing is sent to the browser
during this time.
-The loading time does not really change in real numbers, but the feeling is
-different, because most browsers are able to start rendering incomplete
-content, giving the user a feeling of "it works". This effect is especially
-noticeable on slow dialup connections.
+The loading time typically does not really change much in real numbers, but the
+feeling is different, because most browsers are able to start rendering
+incomplete content, giving the user a feeling of "it works". This effect is
+more noticeable on slower dialup connections. Extremely large documents may
+have some impact on the time to load the page where there is filtering being
+done. But overall, the difference should be very minimal. If there is a big
+impact, then probably some other problem is contributing.
Filtering is automatically disabled for inappropriate MIME types. But note that
if the web server mis-reports the MIME type, then content that should not be
filtered, could be. Privoxy only knows how to differentiate filterable content
because of the MIME type as reported by the server, or because of some
-configuration setting that enables/disables filtering.
+configuration setting that enables/disables filtering.
-------------------------------------------------------------------------------
Note that the built-in URLs from earlier versions of Junkbuster / Privoxy,
http://example.com/show-proxy-args and http://i.j.b/, are no longer supported.
If you still use such an old version, you should really consider upgrading to
-3.0.3.
+3.0.5.
-------------------------------------------------------------------------------
-4.4. Do you still maintain the blocklists?
+4.4. How can I submit new ads, or report problems?
-No. The patterns for blocking now reside (among other things) in the actions
-files, which are actively maintained instead. See next question ...
+Please see the Contact section for various ways to interact with the
+developers.
-------------------------------------------------------------------------------
-4.5. How can I submit new ads?
+4.5. Why doesn't anyone answer my support request?
-Yes, absolutely! Please see the Contact section for how to do that. Please note
-that you (technically) need the latest Privoxy version for this to work.
+Rest assured that it has been read and considered. Why it is not answered,
+could be for various reasons, including no one has a good answer for it, no one
+has had time to yet investigate it thoroughly, it has been reported numerous
+times already, or because not enough information was provided to help us help
+you. Your efforts are not wasted, and we do appreciate them.
-------------------------------------------------------------------------------
4.6. How can I hide my IP address?
If you run both the browser and the proxy locally, you cannot hide your IP
-address with Privoxy or any other software. The server needs to know your IP
-address to send the answers back to you.
-
-Fortunately there are many publicly usable anonymous proxies out there, which
-solve the problem by providing a further level of indirection between you and
-the web server, shared by many people, and thus letting your requests "drown"
-in white noise of unrelated requests as far as user tracking is concerned.
+address with Privoxy or ultimately any other software. The server needs to know
+your IP address so that it knows where to send the responses back.
-Most of them will, however, log your IP address and make it available to the
-authorities in case you abuse that anonymity for criminal purposes. In fact you
-can't even rule out that some of them only exist to *collect* information on
-(those suspicious) people with a more than average preference for privacy.
+There are many publicly usable "anonymous" proxies out there, which provide a
+further level of indirection between you and the web server.
-You can find a list of anonymous public proxies at multiproxy.org and many more
-through Google. A particularly interesting project is the JAP service offered
-by the Technical University of Dresden (http://anon.inf.tu-dresden.de/
-index_en.html).
+However, these proxies are called "anonymous" because you don't need a
+password, not because they would offer any real anonymity. Most of them will
+log your IP address and make it available to the authorities in case you
+violate the law of the country they run in. In fact you can't even rule out
+that some of them only exist to *collect* information on (those suspicious)
+people with a more than average preference for privacy.
-There is, however, even in the single-machine case the possibility to make the
-server believe that your machine is in fact a shared proxy serving a whole big
-LAN, and we are looking into that.
+Your best bet is to chain Privoxy with Tor, an EFF supported onion routing
+system. The configuration details can be found in How do I use Privoxy together
+with Tor section just below.
-------------------------------------------------------------------------------
4.7. Can Privoxy guarantee I am anonymous?
-No. Your chances of remaining anonymous are greatly improved, but unless you
-are an expert on Internet security it would be safest to assume that everything
-you do on the Web can be traced back to you.
+No. Your chances of remaining anonymous are greatly improved, but unless you
+chain Privoxy with Tor or a similar system and know what you're doing when it
+comes to configuring the rest of your system, it would be safest to assume that
+everything you do on the Web can be traced back to you.
Privoxy can remove various information about you, and allows you more freedom
to decide which sites you can trust, and what details you want to reveal. But
-it's still possible that web sites can find out who you are. Here's one way
-this can happen.
+it neither hides your ip address, nor can it guarantee that the rest of the
+system behaves correctly. There are several possibilities how a web sites can
+find out who you are, even if you are using a strict Privoxy configuration and
+chained it with Tor.
+
+Most of Privoxy's protection can be easily subverted by an insecure browser
+configuration, therefore you should use a browser that can be configured to
+only execute code from trusted sites, and be careful which sites you trust. For
+example there is no point in having Privoxy modify the User-Agent header, if
+websites can get all the information they want through JavaScript, ActiveX,
+Flash, Java etc.
A few browsers disclose the user's email address in certain situations, such as
when transferring a file by FTP. Privoxy does not filter FTP. If you need this
-------------------------------------------------------------------------------
-4.8. Might some things break because header information or content is being
+4.8. A test site says I am not using a Proxy.
+
+Good! Actually, they are probably testing for some other kinds of proxies.
+Hiding yourself completely would require additional steps.
+
+-------------------------------------------------------------------------------
+
+4.9. How do I use Privoxy together with Tor?
+
+Before you configure Privoxy to use Tor (http://tor.eff.org/), please follow
+the User Manual chapters 2. Installation and 5. Startup to make sure Privoxy
+itself is setup correctly.
+
+If it is, refer to Tor's extensive documentation to learn how to install Tor,
+and make sure Tor's logfile says that "Tor has successfully opened a circuit"
+and it "looks like client functionality is working".
+
+If either Tor or Privoxy isn't working, their combination most likely will
+neither. Testing them on their own will also help you to direct problem reports
+to the right audience. If Privoxy isn't working, don't bother the Tor
+developers. If Tor isn't working, don't send bug reports to the Privoxy Team.
+
+If you verified that Privoxy and Tor are working, it is time to connect them.
+As far as Privoxy is concerned, Tor is just another proxy that can be reached
+by socks4 or socks4a. Most likely you are interested in Tor to increase your
+anonymity level, therefore you should use socks4a, to make sure Privoxy's DNS
+requests are done through Tor and thus invisible to your local network.
+
+Since Privoxy 3.0.5, its configuration (section 5.2) is already prepared for
+Tor, if you are using a default Tor configuration and run it on the same system
+as Privoxy, you just have to uncomment the line:
+
+# forward-socks4a / 127.0.0.1:9050 .
+
+
+This is enough to reach the Internet, but additionally you should uncomment the
+following forward rules, to make sure your local network is still reachable
+through Privoxy:
+
+# forward 192.168.*.*/ .
+# forward 10.*.*.*/ .
+# forward 127.*.*.*/ .
+
+
+Unencrypted connections to systems in these address ranges will be as (un)
+secure as the local network is, but the alternative is that you can't reach the
+network at all. If you also want to be able to reach servers in your local
+network by using their names, you will need additional exceptions that look
+like this:
+
+# forward localhost/ .
+
+
+Save the modified configuration file and open http://config.privoxy.org/
+show-status/ in your browser, confirm that Privoxy has reloaded its
+configuration and that there are no other forward lines, unless you know that
+you need them. I everything looks good, refer to Tor Faq 4.2 to learn how to
+verify that you are really using Tor.
+
+Afterward, please take the time to at least skim through the rest of Tor's
+documentation. Make sure you understand what Tor does, why it is no replacement
+for application level security, and why you shouldn't use it for unencrypted
+logins.
+
+-------------------------------------------------------------------------------
+
+4.10. Might some things break because header information or content is being
altered?
Definitely. More and more sites use HTTP header content to decide what to
-------------------------------------------------------------------------------
-4.9. Can Privoxy act as a "caching" proxy to speed up web browsing?
+4.11. Can Privoxy act as a "caching" proxy to speed up web browsing?
No, it does not have this ability at all. You want something like Squid for
this. And, yes, before you ask, Privoxy can co-exist with other kinds of
-------------------------------------------------------------------------------
-4.10. What about as a firewall? Can Privoxy protect me?
+4.12. What about as a firewall? Can Privoxy protect me?
Not in the way you mean, or in the way a true firewall can. Privoxy can help
protect your privacy, but not protect you from intrusion attempts. It is, of
-------------------------------------------------------------------------------
-4.11. I have large empty spaces / a checkerboard pattern now where ads used to
+4.13. I have large empty spaces / a checkerboard pattern now where ads used to
be. Why?
It would be technically possible eliminate the banners in a way that frees
-------------------------------------------------------------------------------
-4.12. How can Privoxy filter Secure (HTTPS) URLs?
+4.14. How can Privoxy filter Secure (HTTPS) URLs?
Since secure HTTP connections are encrypted SSL sessions between your browser
and the secure site, and are meant to be reliably secure, there is little that
-------------------------------------------------------------------------------
-4.13. Privoxy runs as a "server". How secure is it? Do I need to take any
+4.15. Privoxy runs as a "server". How secure is it? Do I need to take any
special precautions?
There are no known exploits that might affect Privoxy. On Unix-like systems,
-------------------------------------------------------------------------------
-4.14. How can I temporarily disable Privoxy?
+4.16. How can I temporarily disable Privoxy?
The easiest way is to access Privoxy with your browser by using the remote
toggle URL: http://config.privoxy.org/toggle. See the Bookmarklets section of
-------------------------------------------------------------------------------
-4.15. When "disabled" is Privoxy totally out of the picture?
+4.17. When "disabled" is Privoxy totally out of the picture?
No, this just means all filtering and actions are disabled. Privoxy is still
acting as a proxy, but just not doing any of the things that Privoxy would
-------------------------------------------------------------------------------
-4.16. My logs show Privoxy "crunches" ads, but also its own CGI pages. What is
-a "crunch"?
+4.18. My logs show Privoxy "crunches" ads, but also its own internal CGI pages.
+What is a "crunch"?
A "crunch" simply means Privoxy intercepted something, nothing more. Often this
is indeed ads or banners, but Privoxy uses the same mechanism for trapping
-------------------------------------------------------------------------------
-4.17. Can Privoxy effect files that I download from a webserver? FTP server?
+4.19. Can Privoxy effect files that I download from a webserver? FTP server?
From the webserver's perspective, there is no difference between viewing a
document (i.e. a page), and downloading a file. The same is true of Privoxy. If
Filtering is potentially more of a concern since the results are not always so
obvious, and the effects of filtering are there whether the file is simply
viewed, or downloaded. And potentially whether the content is some obnoxious
-advertizement, or Mr. Jimmy's latest/greatest source code jewel. Of course, one
+advertisement, or Mr. Jimmy's latest/greatest source code jewel. Of course, one
of these presumably is "bad" content that we don't want, and the other is
"good" content that we do want. Privoxy is blind to the differences, and can
only distinguish "good from bad" by the configuration parameters we give it.
file that is intended to be saved to disk, then any content that might have
been altered by filtering, will be saved too, for these (probably rare) cases.
-Note that versions later than 3.0.2 do NOT filter document types of "text/
-plain". Prior to this, Privoxy did filter this document type.
+Note that versions later than 3.0.2 do NOT filter document types reported as
+"text/plain". Prior to this, Privoxy did filter this document type.
In short, filtering is "ON" if a) the Document Type as reported by the
webserver is appropriate and b) the configuration allows it (or at least does
3.0.2 or earlier) in your user.action file. And also, for any site or page
where making any changes at all to the content is to be avoided.
-Privoxy does not do FTP at all, only HTTP protocols, so please don't even try.
+Privoxy does not do FTP at all, only HTTP and HTTPS (SSL) protocols, so please
+don't try.
-------------------------------------------------------------------------------
-4.18. I just downloaded a Perl script, and Privoxy altered it! Yikes, what is
+4.20. I just downloaded a Perl script, and Privoxy altered it! Yikes, what is
wrong!
Please read above.
-------------------------------------------------------------------------------
-4.19. Where can I find more information about Privoxy and related issues?
+4.21. Should I continue to use a "HOSTS" file for ad-blocking?
+
+One time-tested technique to defeat common ads is to trick the local DNS system
+by giving a phony IP address for the ad generator in the local HOSTS file,
+typically using 127.0.0.1, aka localhost. This effectively blocks the ad.
+
+There is no reason to use this technique in conjunction with Privoxy. Privoxy
+does essentially the same thing, much more elegantly and with much more
+flexibility. A large HOSTS file, in fact, not only duplicates effort, but may
+get in the way. It is recommended to remove such entries from your HOSTS file.
+If you think your hosts list is neglected by Privoxy's configuration, consider
+adding your list to your user.action file:
+
+ { +block }
+ www.ad.example1.com
+ ad.example2.com
+ ads.galore.example.com
+ etc.example.com
+
+-------------------------------------------------------------------------------
+
+4.22. Where can I find more information about Privoxy and related issues?
Other references and sites of interest to Privoxy users:
http://www.privoxy.org/faq/, the Privoxy FAQ.
-http://sourceforge.net/projects/ijbswa/, the Project Page for Privoxy on
-SourceForge.
+http://sourceforge.net/projects/ijbswa/, the Project Page for Privoxy on
+SourceForge.
-http://config.privoxy.org/, the web-based user interface. Privoxy must be
-running for this to work. Shortcut: http://p.p/
+http://config.privoxy.org/, the web-based user interface. Privoxy must be
+running for this to work. Shortcut: http://p.p/
-http://www.privoxy.org/actions/, to submit "misses" to the developers.
+http://sourceforge.net/tracker/?group_id=11118&atid=460288, to submit "misses"
+and other configuration related suggestions to the developers.
-http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/ijbswa/contrib/, cool and fun
-ideas from Privoxy users.
-
-http://www.junkbusters.com/ht/en/cookies.html, an explanation how cookies are
-used to track web users.
+http://www.junkbusters.com/ht/en/cookies.html, an explanation how cookies are
+used to track web users.
http://www.junkbusters.com/ijb.html, the original Internet Junkbuster.
-http://www.waldherr.org/junkbuster/, Stefan Waldherr's version of Junkbuster,
-from which Privoxy was derived.
+http://privacy.net/, a useful site to check what information about you is
+leaked while you browse the web.
-http://privacy.net/analyze/, a useful site to check what information about you
-is leaked while you browse the web.
+http://www.squid-cache.org/, a very popular caching proxy, which is often used
+together with Privoxy.
-http://www.squid-cache.org/, a very popular caching proxy, which is often used
-together with Privoxy.
+http://tor.eff.org/, Tor can help anonymize web browsing, web publishing,
+instant messaging, IRC, SSH, and other applications.
http://www.privoxy.org/developer-manual/, the Privoxy developer manual.
-------------------------------------------------------------------------------
-4.20. I've noticed that Privoxy changes "Microsoft" to "MicroSuck"! Why are you
+4.23. I've noticed that Privoxy changes "Microsoft" to "MicroSuck"! Why are you
manipulating my browsing?
We're not. The text substitutions that you are seeing are disabled in the
default configuration as shipped. You have either manually activated the "fun"
filter which is clearly labeled "Text replacements for subversive browsing fun!
-" or you have implicitly activated it by choosing the "Adventuresome" profile
-in the web-based editor (formerly known as the Advanced profile).
+" or you are using an older Privoxy version and have implicitly activated it by
+choosing the "Adventuresome" profile in the web-based editor. Please upgrade!
-------------------------------------------------------------------------------
5. Troubleshooting
-5.1. I just upgraded and am getting "connection refused" with every web page?
+5.1. I am getting "connection refused" with every web page?
Either Privoxy is not running, or your browser is configured for a different
-port than what Privoxy is using.
+port than what Privoxy is using, or, if using a forwarding rule, you have a
+configuration problem or a problem with a host in the forwarding chain.
-The old Privoxy (and also Junkbuster) used port 8000 by default. This has been
-changed to port 8118 now, due to a conflict with NAS (Network Audio Service),
-which uses port 8000. If you haven't, you need to change your browser to the
-new port number, or alternately change the listen-address option in Privoxy's
-main configuration file.
+You should verify that Privoxy is indeed running and that the correct port is
+set, and matches what your browser is set to. See listen-address option in
+Privoxy's main configuration file. If using any forwarding rules, disable those
+to make sure the problem is not with a forwarder.
-------------------------------------------------------------------------------
If this doesn't help, you probably have an error in the rule you applied. Try
pasting the full URL of the offending ad into http://config.privoxy.org/
-show-url-info and see if it really matches your new rule.
+show-url-info and see if it really matches your new rule. Blocking ads is like
+blocking spam: a lot of tinkering is required to stay ahead of the game.
-------------------------------------------------------------------------------
actions, but is also likely to turn off more actions then needed, and thus
lower your privacy and protection more than necessary,
-Troubleshooting actions is discussed in more detail in the user-manual appendix
-. There is also an actions tutorial.
+Troubleshooting actions is discussed in more detail in the User Manual
+appendix, Troubleshooting: the Anatomy of an Action. There is also an actions
+tutorial with general configuration information and examples.
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
-5.5. I cannot connect to any FTP sites. Privoxy seems to be blocking me.
+5.5. I cannot connect to any FTP sites. Privoxy is blocking me.
Privoxy cannot act as a proxy for FTP traffic, so do not configure your browser
to use Privoxy as an FTP proxy. The same is true for any protocol other than
-HTTP or HTTPS.
+HTTP or HTTPS (SSL).
Most browsers understand FTP as well as HTTP. If you connect to a site, with a
URL like ftp://ftp.example.com, your browser is making an FTP connection, and
and cannot proxy such traffic.
To complicate matters, some systems may have a generic "proxy" setting, which
-will silently enable both HTTP and FTP proxying! So it is possible to
-accidentally enable FTP proxying in these cases. And of course, if this
-happens, Privoxy will indeed cause problems since it does not know FTP.
+will silently enable various protocols, including both HTTP and FTP proxying!
+So it is possible to accidentally enable FTP proxying in these cases. And of
+course, if this happens, Privoxy will indeed cause problems since it does not
+know FTP. Newer version will give a sane error message if a FTP connection is
+attempted. Just disable the FTP setting and all will be well again.
Will Privoxy ever proxy FTP traffic? Unlikely. There just is not much reason,
and the work to make this happen is more than it may seem.
To find out if this is in fact the source of the problem, try adding the site
to a -prevent-compression section in user.action:
- # Make exceptions for ill-behaved sites:
- #
- {-prevent-compression}
- .example.com
-
+ # Make exceptions for ill-behaved sites:
+ #
+ {-prevent-compression}
+ .example.com
If that works, you may also want to report the problem to the site's
webmasters, telling them to use zlib.output_compression instead of ob_gzhandler
5.10. Why am I getting a 503 Error (WSAECONNREFUSED) on every page?
-More than likely this is a problem with the network stack. ZoneAlarm has been
-reported to cause this symptom -- even if not running. The solution is to
+More than likely this is a problem with your TCP/IP networking. ZoneAlarm has
+been reported to cause this symptom -- even if not running. The solution is to
either fight the ZA configuration, or uninstall ZoneAlarm, and then find
-something better behaved in its place. Other firewall type products may cause
-similar type problems if not configured correctly.
+something better behaved in its place. Other personal firewall type products
+may cause similar type problems if not configured correctly.
-------------------------------------------------------------------------------
listen-address setting). If the system cannot supply this information, Privoxy
logs this condition.
-Typically, this would be considered a system configuration error. It is not a
-fatal error to Privoxy however, but may result in a much slower response from
-Privoxy due to DNS timeouts.
+Typically, this would be considered a minor system configuration error. It is
+not a fatal error to Privoxy however, but may result in a much slower response
+from Privoxy on some platforms due to DNS timeouts.
+
+This can be caused by a problem with the local HOSTS file. If this file has
+been changed from the original, try reverting it to see if that helps.
-------------------------------------------------------------------------------
Port 8118 is Privoxy's default TCP "listening" port. Typically this message
would mean that there is already one instance of Privoxy running, and you are
actually trying to start a second Privoxy on the same port, which will not
-work. How and why this might happen varies from platform to platform, but you
+work. (You can have multiple instances but they must be assigned different
+ports.) How and why this might happen varies from platform to platform, but you
need to check your installation and start-up procedures.
-------------------------------------------------------------------------------
5.13. Pages with UTF-8 fonts are garbled.
-This is caused by the "demoronizer" filter, which was introduced in version
-3.0.2, and was inappropriately turned on by default. You should either upgrade
-Privoxy, or at least upgrade to the most recent default.action file available
-from SourceForge. Or you can simply disable the demoronizer filter.
+This is caused by the "demoronizer" filter. You should either upgrade Privoxy,
+or at least upgrade to the most recent default.action file available from
+SourceForge. Or you can simply disable the demoronizer filter.
-------------------------------------------------------------------------------
This may also be caused by the "demoronizer" filter, in conjunction with a web
server that is misreporting a file type. Binary files are exempted from
-Privoxy's filtering (unless the web server by mistake says the file is a plain
-text file). Either upgrade Privoxy, or go to the most recent default.action
-file available from SourceForge.
+Privoxy's filtering (unless the web server by mistake says the file is
+something else). Either upgrade Privoxy, or go to the most recent
+default.action file available from SourceForge.
-------------------------------------------------------------------------------
On the other hand, if you use non-Microsoft products, and you occasionally
notice wierd characters on pages, you might want to try it.
-This filter was introduced with version 3.0.2 of Privoxy, and was on by default
-in that version. It is off in all subsequent versions (unless turned on by the
-user).
-
-------------------------------------------------------------------------------
5.16. Why do I keep seeing "PrivoxyWindowOpen()" in raw source code?
-------------------------------------------------------------------------------
+5.17. I am getting too many DNS errors like "404 No Such Domain". Why can't
+Privoxy do this better?
+
+There are potentially several factors here. First of all, the DNS resolution is
+done by the underlying operating system -- not Privoxy itself. Privoxy merely
+initiates the process and hands it off, and then later reports whatever the
+outcome was. And tries to give a coherent message if there seems to be a
+problem. In some cases, this might otherwise be mitigated by the browser itself
+which might try some work-arounds and alternate approaches (e.g adding "www."
+to the URL). In other cases, if Privoxy is being chained with another proxy,
+this could complicate the issue, and cause undue delays and timeouts. In the
+case of a "socks4a" proxy, the socks server handles all the DNS. Privoxy would
+just be the "messenger" which is reporting whatever problem occurred
+downstream, and not the root cause of the error.
+
+In any case, v. 3.0.5 includes various improvements to help Privoxy better
+handle these cases.
+
+-------------------------------------------------------------------------------
+
+5.18. At one site Privoxy just hangs, and starts taking all CPU. Why is this?
+
+This is probably a manifestation of the "100% cpu" problem that occurs on pages
+containing many (thousands upon thousands) of blank lines. The blank lines are
+in the raw HTML source of the page, and the browser just ignores them. But the
+pattern matching in Privoxy's page filtering mechanism is trying to match
+against absurdly long strings and this becomes very CPU-intensive, taking a
+long, long time to complete. Until a better solution comes along, disable
+filtering on these pages, particularly the js-annoyances and unsolicited-popups
+filters.
+
+-------------------------------------------------------------------------------
+
+5.19. I just installed Privoxy, and all my browsing has slowed to a crawl. What
+gives?
+
+This should not happen, and for the overwhelming number of users world-wide, it
+does not happen. I would suspect some inadvertent interaction of software
+components such as anti-virus software, spyware protectors, personal firewalls
+or similar components. Try disabling (or uninstalling) these one at a time and
+see if that helps.
+
+-------------------------------------------------------------------------------
+
6. Contacting the developers, Bug Reporting and Feature Requests
We value your feedback. In fact, we rely on it to improve Privoxy and its
6.1. Get Support
-For casual users, our support forum at SourceForge is probably best suited:
+For casual users, our support forum at SourceForge is probably best suited:
http://sourceforge.net/tracker/?group_id=11118&atid=211118
All users are of course welcome to discuss their issues on the users mailing
-------------------------------------------------------------------------------
-6.2. Report Bugs
+6.2. Reporting Problems
+
+"Problems" for our purposes, come in two forms:
+
+ * Configuration issues, such as ads that slip through, or sites that don't
+ function properly due to one Privoxy "action" or another being turned "on".
+
+ * "Bugs" in the programming code that makes up Privoxy, such as that might
+ cause a crash.
+
+-------------------------------------------------------------------------------
+
+6.2.1. Reporting Ads or Other Configuration Problems
+
+Please send feedback on ads that slipped through, innocent images that were
+blocked, sites that don't work properly, and other configuration related
+problem of default.action file, to http://sourceforge.net/tracker/?group_id=
+11118&atid=460288, the Actions File Tracker.
+
+New, improved default.action files may occasionally be made available based on
+your feedback. These will be announced on the ijbswa-announce list and
+available from our the files section of our project page.
+
+-------------------------------------------------------------------------------
+
+6.2.2. Reporting Bugs
Please report all bugs only through our bug tracker: http://sourceforge.net/
tracker/?group_id=11118&atid=111118.
Before doing so, please make sure that the bug has not already been submitted
-and observe the additional hints at the top of the submit form.
+and observe the additional hints at the top of the submit form. If already
+submitted, please feel free to add any info to the original report that might
+help to solve the issue.
Please try to verify that it is a Privoxy bug, and not a browser or site bug
-first. If unsure, try toggling off Privoxy, and see if the problem persists.
-The appendix of the user manual also has helpful information on action
-debugging. If you are using your own custom configuration, please try the stock
-configs to see if the problem is configuration related.
-
-If not using the latest version, chances are that the bug has been found and
-fixed in the meantime. We would appreciate if you could take the time to
-upgrade to the latest version (or even the latest CVS snapshot) and verify your
-bug, but this is not required for reporting.
+first. If unsure, try toggling off Privoxy, and see if the problem persists. If
+you are using your own custom configuration, please try the stock configs to
+see if the problem is configuration related.
+
+If not using the latest version, the bug may have been found and fixed in the
+meantime. We would appreciate if you could take the time to upgrade to the
+latest version (or even the latest CVS snapshot) and verify your bug.
+
+Please be sure to provide the following information:
+
+ * The exact Privoxy version of the proxy software (if you got the source from
+ CVS, please also provide the source code revisions as shown in http://
+ config.privoxy.org/show-version).
+
+ * The operating system and versions you run Privoxy on, (e.g. Windows XP
+ SP2), if you are using some kind of Unix flavour, sending the output of
+ "uname -a" should do.
+
+ * The name, platform, and version of the browser you were using (e.g.
+ Internet Explorer v5.5 for Mac).
+
+ * The URL where the problem occurred, or some way for us to duplicate the
+ problem (e.g. http://somesite.example.com/?somethingelse=123).
+
+ * Whether your version of Privoxy is one supplied by the developers of
+ Privoxy via SourceForge, or somewhere else.
+
+ * Whether you are using Privoxy in tandem with another proxy such as Tor. If
+ so, please try disabling the other proxy.
+
+ * Whether you are using a personal firewall product. If so, does Privoxy work
+ without it?
+
+ * Any other pertinent information to help identify the problem such as config
+ or log file excerpts (yes, you should have log file entries for each action
+ taken).
+
+ * Please provide your SF login, or email address, in case we need to contact
+ you.
+
+The appendix of the Privoxy User Manual also has helpful information on
+understanding actions, and action debugging.
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
-6.4. Report Ads or Other Actions-Related Problems
-
-Please send feedback on ads that slipped through, innocent images that were
-blocked, and any other problems relating to the default.action file through our
-actions feedback mechanism located at http://www.privoxy.org/actions/. On this
-page, you will also find a bookmark which will take you back there from any
-troubled site and even pre-fill the form!
-
-New, improved default.action files will occasionally be made available based on
-your feedback. These will be announced on the ijbswa-announce list and
-available from our the files section of our project page.
-
--------------------------------------------------------------------------------
-
-6.5. Other
+6.4. Other
For any other issues, feel free to use the mailing lists. Technically
interested users and people who wish to contribute to the project are also
7. Privoxy Copyright, License and History
-Copyright © 2001 - 2004 by Privoxy Developers <developers@privoxy.org>
+Copyright © 2001 - 2006 by Privoxy Developers <
+ijbswa-developers@lists.sourceforge.net>
Some source code is based on code Copyright © 1997 by Anonymous Coders and
Junkbusters, Inc. and licensed under the GNU General Public License.
This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE. See the GNU General Public License for more details, which
-is available from the Free Software Foundation, Inc, 59 Temple Place - Suite
-330, Boston, MA 02111-1307, USA.
+is available from the Free Software Foundation, Inc, 51 Franklin Street, Fifth
+Floor, Boston, MA 02110-1301, USA
You should have received a copy of the GNU General Public License along with
this program; if not, write to the
Free Software
- Foundation, Inc. 59 Temple Place - Suite 330
- Boston, MA 02111-1307
+ Foundation, Inc. 51 Franklin Street, Fifth Floor
+ Boston, MA 02110-1301
USA
-------------------------------------------------------------------------------
7.2. History
-In the beginning, there was the Internet Junkbuster, by Anonymous Coders and
-Junkbusters Corporation. It saved many users a lot of pain in the early days of
-web advertising and user tracking.
+Along time ago, there was the Internet Junkbuster, by Anonymous Coders and
+Junkbusters Corporation. This saved many users a lot of pain in the early days
+of web advertising and user tracking.
But the web, its protocols and standards, and with it, the techniques for
-forcing users to consume ads, give up autonomy over their browsing, and for
-spying on them, kept evolving. Unfortunately, the Internet Junkbuster did not.
-Version 2.0.2, published in 1998, was (and is) the last official release
-available from Junkbusters Corporation. Fortunately, it had been released under
-the GNU GPL, which allowed further development by others.
+forcing ads on users, give up autonomy over their browsing, and for tracking
+them, keeps evolving. Unfortunately, the Internet Junkbuster did not. Version
+2.0.2, published in 1998, was (and is) the last official release available from
+Junkbusters Corporation. Fortunately, it had been released under the GNU GPL,
+which allowed further development by others.
So Stefan Waldherr started maintaining an improved version of the software, to
which eventually a number of people contributed patches. It could already
projects / privoxy.git / blobdiff