1 Privoxy Frequently Asked Questions
3 Copyright © 2001, 2002 by Privoxy Developers
5 $Id: faq.sgml,v 1.61.2.27 2002/12/01 06:31:58 hal9 Exp $
7 This FAQ gives quick answers to frequently asked questions about Privoxy. It
8 can't and doesn't replace the User Manual.
10 Privoxy is a web proxy with advanced filtering capabilities for protecting
11 privacy, filtering web page content, managing cookies, controlling access, and
12 removing ads, banners, pop-ups and other obnoxious Internet junk. Privoxy has a
13 very flexible configuration and can be customized to suit individual needs and
14 tastes. Privoxy has application for both stand-alone systems and multi-user
17 Privoxy is based on Internet Junkbuster (tm).
19 Please note that this document is constantly evolving. This copy represents the
20 state at the release of version 0.0.0. You can find the latest version of the
21 document at http://www.privoxy.org/faq/. Please see the Contact section if you
22 want to contact the developers.
24 -------------------------------------------------------------------------------
27 1. General Information
29 1.1. What is this new version of Privoxy?
30 1.2. Why "Privoxy"? Why a name change at all?
31 1.3. How does Privoxy differ from the old Junkbuster?
32 1.4. What is a "proxy"? How does Privoxy work?
33 1.5. How does Privoxy know what is an ad, and what is not?
34 1.6. Can Privoxy make mistakes? This does not sound very scientific.
35 1.7. My browser does the same things as Privoxy. Why should I use Privoxy
37 1.8. Is there is a license or fee? What about a warranty? Registration?
38 1.9. I would like to help you, what do I do?
40 1.9.1. Money Money Money
42 1.9.3. You want to work with us?
46 2.1. Which browsers are supported by Privoxy?
47 2.2. Which operating systems are supported?
48 2.3. Can I use Privoxy with my email client?
49 2.4. Can I install Privoxy over Junkbuster?
50 2.5. I just installed Privoxy. Is there anything special I have to do now?
51 2.6. What is the proxy address of Privoxy?
52 2.7. I just installed Privoxy, and nothing is happening. All the ads are
57 3.1. Where can I get updated Actions Files?
58 3.2. Can I use my old config files?
59 3.3. What is an "actions" file?
60 3.4. The "actions" concept confuses me. Please list some of these
62 3.5. How are actions files configured? What is the easiest way to do this?
63 3.6. There are several different "actions" files. What are the differences?
64 3.7. How can I make my Yahoo/Hotmail/GMX account work?
65 3.8. What's the difference between the "Cautious", "Medium" and "Radical"
67 3.9. Why can I change the configuration with a browser? Does that not raise
69 3.10. What is the default.filter file? What is a "filter"?
70 3.11. How can I set up Privoxy to act as a proxy for my LAN?
71 3.12. Instead of ads, now I get a checkerboard pattern. I don't want to see
73 3.13. Why would anybody want to see a checkerboard pattern?
74 3.14. I see some images being replaced by a text instead of the
75 checkerboard image. Why and how do I get rid of this?
76 3.15. Can Privoxy run as a service on Win2K/NT?
77 3.16. How can I make Privoxy work with other proxies like Squid?
78 3.17. Can I just set Privoxy to use port 80 and thus avoid individual
79 browser configuration?
80 3.18. Can Privoxy run as a "transparent" proxy?
81 3.19. How can I configure Privoxy for use with Outlook Express?
82 3.20. How can I have separate rules just for HTML mail?
83 3.21. How can I allow permanent cookies for my trusted sites?
87 4.1. How much does Privoxy slow my browsing down? This has to add extra
89 4.2. I noticed considerable delays in page requests compared to the old
90 Junkbuster. What's wrong?
91 4.3. What are "http://config.privoxy.org/" and "http://p.p/"?
92 4.4. Do you still maintain the blocklists?
93 4.5. How can I submit new ads?
94 4.6. How can I hide my IP address?
95 4.7. Can Privoxy guarantee I am anonymous?
96 4.8. Might some things break because header information or content is being
98 4.9. Can Privoxy act as a "caching" proxy to speed up web browsing?
99 4.10. What about as a firewall? Can Privoxy protect me?
100 4.11. I have large empty spaces / a checkerboard pattern now where ads used
102 4.12. How can Privoxy filter Secure (HTTPS) URLs?
103 4.13. Privoxy runs as a "server". How secure is it? Do I need to take any
105 4.14. How can I temporarily disable Privoxy?
106 4.15. When "disabled" is Privoxy totally out of the picture?
107 4.16. My logs show Privoxy "crunches" ads, but also its own CGI pages. What
109 4.17. Can Privoxy effect files that I download from a webserver? FTP
111 4.18. Where can I find more information about Privoxy and related issues?
112 4.19. I've noticed that Privoxy changes "Microsoft" to "MicroSuck"! Why are
113 you manipulating my browsing?
117 5.1. I just upgraded and am getting "connection refused" with every web
119 5.2. I just added a new rule, but the steenkin ad is still getting through.
121 5.3. One of my favorite sites does not work with Privoxy. What can I do?
122 5.4. After installing Privoxy, I have to log in every time I start IE. What
124 5.5. I cannot connect to any FTP sites. Privoxy seems to be blocking me.
125 5.6. In Mac OSX, I can't configure Microsoft Internet Explorer to use
126 Privoxy as the HTTP proxy.
127 5.7. In Mac OSX, I dragged the Privoxy folder to the trash in order to
128 uninstall it. Now the finder tells me I don't have sufficient
129 privileges to empty the trash.
130 5.8. I get a completely blank page at one site. "View Source" shows only:
131 <html><body></body></html>. Without Privoxy the page loads fine.
132 5.9. Why am I getting a 503 Error (WSAECONNREFUSED) on every page?
134 6. Contacting the developers, Bug Reporting and Feature Requests
138 6.3. Request New Features
139 6.4. Report Ads or Other Actions-Related Problems
142 7. Privoxy Copyright, License and History
147 1. General Information
149 1.1. What is this new version of Privoxy?
151 In the beginning, there was the Internet Junkbuster, by Anonymous Coders and
152 Junkbusters Corporation. It saved many users a lot of pain in the early days of
153 web advertising and user tracking.
155 But the web, its protocols and standards, and with it, the techniques for
156 forcing users to consume ads, give up autonomy over their browsing, and for
157 spying on them, kept evolving. Unfortunately, the Internet Junkbuster did not.
158 Version 2.0.2, published in 1998, was (and is) the last official release
159 available from Junkbusters Corporation. Fortunately, it had been released under
160 the GNU GPL, which allowed further development by others.
162 So Stefan Waldherr started maintaining an improved version of the software, to
163 which eventually a number of people contributed patches. It could already
164 replace banners with a transparent image, and had a first version of pop-up
165 killing, but it was still very closely based on the original, with all its
166 limitations, such as the lack of HTTP/1.1 support, flexible per-site
167 configuration, or content modification. The last release from this effort was
168 version 2.0.2-10, published in 2000.
170 Then, some developers picked up the thread, and started turning the software
171 inside out, upside down, and then reassembled it, adding many new features
174 The result of this is Privoxy, whose first stable release, 3.0, was released
177 -------------------------------------------------------------------------------
179 1.2. Why "Privoxy"? Why a name change at all?
181 Privoxy is the "Privacy Enhancing Proxy". Also, its content modification and
182 junk suppression allow you to browse your "private edition" of the web.
184 Junkbusters Corporation continues to offer their original version of the
185 Internet Junkbuster, so publishing our Junkbuster-derived software under the
186 same name led to confusion.
188 There are also potential legal complications from the continued use of the
189 Junkbuster name, which is a registered trademark of Junkbusters Corporation.
190 There are, however, no objections from Junkbusters Corporation to the Privoxy
191 project itself, and they, in fact, still share our ideals and goals.
193 The developers also believed that there are so many changes from the original
194 code, that it was time to make a clean break from the past and make a name in
195 their own right, especially now with the pending release of version 3.0.
197 -------------------------------------------------------------------------------
199 1.3. How does Privoxy differ from the old Junkbuster?
201 Privoxy picks up where Junkbuster left off. All the old features remain. The
202 new Privoxy still blocks ads and banners, still manages cookies, and still
203 helps protect your privacy. But, these are all enhanced, and many new features
204 have been added, all in the same vein.
206 The configuration has changed significantly as well. This is something that
207 users will notice right off the bat if upgrading from Junkbuster 2.0.x. The
208 "blocklist" "cookielist", "imagelist" and much more has been combined into the
209 "actions" files, with a completely different syntax. See the note to upgraders
212 Privoxy's new features include:
214 * Integrated browser based configuration and control utility at http://
215 config.privoxy.org/ (shortcut: http://p.p/). Browser-based tracing of rule
216 and filter effects. Remote toggling.
218 * Web page content filtering (removes banners based on size, invisible
219 "web-bugs", JavaScript and HTML annoyances, pop-up windows, etc.)
221 * Modularized configuration that allows for standard settings and user
222 settings to reside in separate files, so that installing updated actions
223 files won't overwrite individual user settings.
225 * HTTP/1.1 compliant (but not all optional 1.1 features are supported).
227 * Support for Perl Compatible Regular Expressions in the configuration files,
228 and generally a more sophisticated and flexible configuration syntax over
231 * Improved cookie management features (e.g. session based cookies).
235 * Bypass many click-tracking scripts (avoids script redirection).
237 * Multi-threaded (POSIX and native threads).
239 * User-customizable HTML templates for all proxy-generated pages (e.g.
242 * Auto-detection and re-reading of config file changes.
244 * Improved signal handling, and a true daemon mode (Unix).
246 * Every feature now controllable on a per-site or per-location basis,
247 configuration more powerful and versatile over-all.
249 * Many smaller new features added, limitations and bugs removed, and security
252 -------------------------------------------------------------------------------
254 1.4. What is a "proxy"? How does Privoxy work?
256 A web proxy is a service, based on a software such as Privoxy, that clients
257 (i.e. browsers) can use instead of connecting directly to the web servers on
258 the Internet. The clients then ask the proxy to fetch the objects they need
259 (web pages, images, movies etc) on their behalf, and when the proxy has done
260 so, it hands the results back to the client.
262 There are many reasons to use web proxies, such as security (firewalling),
263 efficiency (caching) and others, and there are just as many different proxies
264 to accommodate those needs.
266 Privoxy is a proxy that is solely focused on privacy protection and junk
267 elimination. Sitting between your browser(s) and the Internet, it is in a
268 perfect position to filter outbound personal information that your browser is
269 leaking, as well as inbound junk. It uses a variety of techniques to do this,
270 all of which are under your control via the various configuration files and
273 -------------------------------------------------------------------------------
275 1.5. How does Privoxy know what is an ad, and what is not?
277 Privoxy's approach to blocking ads is twofold:
279 First, there are certain patterns in the locations (URLs) of banner images.
280 This applies to both the path (you wouldn't guess how many web sites serve
281 their banners from a directory called "banners"!) and the host (blocking the
282 big banner hosting services like doublecklick.net already helps a lot). Privoxy
283 takes advantage of this fact by using URL patterns to sort out and block the
284 requests for banners.
286 Second, banners tend to come in certain sizes. But you can't tell the size of
287 an image by its URL without downloading it, and if you do, it's too late to
288 save bandwidth. Therefore, Privoxy also inspects the HTML sources of web pages
289 while they are loaded, and replaces references to images with standard banner
290 sizes by dummy references, so that your browser doesn't request them anymore in
293 Both of this involves a certain amount of guesswork and is, of course, freely
296 -------------------------------------------------------------------------------
298 1.6. Can Privoxy make mistakes? This does not sound very scientific.
300 Actually, it's a black art ;-) And yes, it is always possible to have a broad
301 rule accidentally block or change something by mistake. There is a good chance
302 you may run into such a situation at some point. It is tricky writing rules to
303 cover every conceivable possibility, and not occasionally get false positives.
305 But this should not be a big concern since the Privoxy configuration is very
306 flexible, and includes tools to help identify these types of situations so they
307 can be addressed as needed, allowing you to customize your installation. (See
308 the Troubleshooting section below.)
310 -------------------------------------------------------------------------------
312 1.7. My browser does the same things as Privoxy. Why should I use Privoxy at
315 Modern browsers do indeed have some of the same functionality as Privoxy. Maybe
316 this is adequate for you. But Privoxy is much more versatile and powerful, and
317 can do a number of things that browsers just can't.
319 In addition, a proxy is good choice if you use multiple browsers, or have a LAN
320 with multiple computers. This way all the configuration is in one place, and
321 you don't have to maintain a similar configuration for possibly many browsers.
323 -------------------------------------------------------------------------------
325 1.8. Is there is a license or fee? What about a warranty? Registration?
327 Privoxy is licensed under the GNU General Public License (GPL). It is free to
328 use, copy, modify or distribute as you wish under the terms of this license.
329 Please see the Copyright section for more information on the license and
330 copyright. Or the LICENSE file that should be included.
332 There is no warranty of any kind, expressed, implied or otherwise. That is
333 something that would cost real money ;-) There is no registration either.
334 Privoxy really is free in every respect!
336 -------------------------------------------------------------------------------
338 1.9. I would like to help you, what do I do?
340 1.9.1. Money Money Money
342 We, of course, welcome donations and could use money for domain registering,
343 buying software to test Privoxy with, and, of course, for regular world-wide
344 get-togethers (hahaha). If you enjoy the software and feel like helping us with
345 a donation, just drop us a note.
347 -------------------------------------------------------------------------------
351 If you are a vendor of a web-related software like a browser, web server or
352 proxy, and would like us to ensure that Privoxy runs smoothly with your
353 product, you might consider supplying us with a copy or license. We can't,
354 however, guarantee that we will fix all potential compatibility issues as a
357 -------------------------------------------------------------------------------
359 1.9.3. You want to work with us?
361 Well, helping the team is always a good idea. We welcome new developers,
362 packaging gurus or documentation writers. Simply get an account on
363 SourceForge.net and mail your id to the developers mailing list. Then read the
366 Once we have added you to the team, you'll have write access to the CVS
367 repository, and together we'll find a suitable task for you.
369 -------------------------------------------------------------------------------
373 2.1. Which browsers are supported by Privoxy?
375 Any browser that can be configured to use a proxy, which should be virtually
376 all browsers. Direct browser support is not necessary since Privoxy runs as a
377 separate application and talks to the browser in the standardized HTTP
378 protocol, just like a web server does.
380 -------------------------------------------------------------------------------
382 2.2. Which operating systems are supported?
384 At present, Privoxy is known to run on Windows(95, 98, ME, 2000, XP), Linux
385 (RedHat, SuSE, Debian, Conectiva, Gentoo, Slackware), Mac OSX, OS/2, AmigaOS,
386 BeOS, FreeBSD, NetBSD, OpenBSD, Solaris, and many more flavors of Unix.
388 But any operating system that runs TCP/IP, can conceivably take advantage of
389 Privoxy in a networked situation where Privoxy would run as a server on a LAN
390 gateway. Then only the "gateway" needs to be running one of the above operating
393 Source code is freely available, so porting to other operating systems is
394 always a possibility.
396 -------------------------------------------------------------------------------
398 2.3. Can I use Privoxy with my email client?
400 As long as there is some way to set a HTTP proxy for the client, then yes, any
401 application can be used, whether it is strictly speaking a "browser" or not.
402 Though this may not be the best approach for dealing with some of the common
403 abuses of HTML in email. See How can I configure Privoxy with Outlook Express?
404 below for more on this.
406 Be aware that HTML email presents a number of unique security and privacy
407 related issues, that can require advanced skills to overcome. The developers
408 recommend using email clients that can be configured to convert HTML to plain
409 text for these reasons.
411 -------------------------------------------------------------------------------
413 2.4. Can I install Privoxy over Junkbuster?
415 We recommend you un-install Junkbuster first to minimize conflicts and
416 confusion. You may want to save your old configuration files for future
417 reference. The configuration files and syntax have substantially changed, so
418 you will need to manually port your old patterns. See the note to upgraders and
419 installation chapter in the user manual for details.
421 Note: Some installers may automatically un-install Junkbuster, if present!
423 -------------------------------------------------------------------------------
425 2.5. I just installed Privoxy. Is there anything special I have to do now?
427 All browsers must be told to use Privoxy as a proxy by specifying the correct
428 proxy address and port number in the appropriate configuration area for the
429 browser. See below. You should also flush your browser's memory and disk cache
430 to get rid of any cached junk items, and remove any stored cookies.
432 -------------------------------------------------------------------------------
434 2.6. What is the proxy address of Privoxy?
436 If you set up the Privoxy to run on the computer you browse from (rather than
437 your ISP's server or some networked computer on a LAN), the proxy will be on
438 127.0.0.1 (sometimes referred to as "localhost", which is the special name used
439 by every computer on the Internet to refer to itself) and the port will be 8118
440 (unless you have Privoxy to run on a different port with the listen-address
443 When configuring your browser's proxy settings you typically enter the word
444 "localhost" or the IP address "127.0.0.1" in the boxes next to "HTTP" and
445 "Secure" (HTTPS) and then the number "8118" for "port". This tells your browser
446 to send all web requests to Privoxy instead of directly to the Internet.
448 Privoxy can also be used to proxy for a Local Area Network. In this case, your
449 would enter either the IP address of the LAN host where Privoxy is running, or
450 the equivalent hostname. Port assignment would be same as above. Note that
451 Privoxy doesn't listen on any LAN interfaces by default.
453 Privoxy does not currently handle protocols such as FTP, SMTP, IM, IRC, ICQ, or
454 other Internet protocols.
456 -------------------------------------------------------------------------------
458 2.7. I just installed Privoxy, and nothing is happening. All the ads are there.
461 Did you configure your browser to use Privoxy as a proxy? It does not sound
462 like it. See above. You might also try flushing the browser's caches to force a
463 full re-reading of pages. You can verify that Privoxy is running, and your
464 browser is correctly configured by entering the special URL: http://
465 config.privoxy.org/. This should take you to a page titled "This is Privoxy.."
466 with access to Privoxy's internal configuration. If you see this, then you are
467 good to go. If you receive a page saying "Privoxy is not running", then the
468 browser is not set up to use your Privoxy installation. If you receive anything
469 else (probably nothing at all), it could either be that the browser is not set
470 up correctly, or that Privoxy is not running at all. Check the log file.
472 -------------------------------------------------------------------------------
476 3.1. Where can I get updated Actions Files?
478 Based on your feedback and the continuing development, updated actions files
479 will be made available on the files section of our project page.
481 If you wish to receive an email notification whenever we release updates of
482 Privoxy or the actions file, subscribe to our announce mailing list,
483 ijbswa-announce@lists.sourceforge.net.
485 -------------------------------------------------------------------------------
487 3.2. Can I use my old config files?
489 The syntax, number, and purpose of configuration files has substantially
490 changed from Junkbuster and earlier versions of Privoxy. The old files, like
491 blocklist will not work at all. If you are upgrading from a 2.0.x version, you
492 will need to port your configuration data to the new format. Note that even the
493 pattern syntax has changed! Even configuration files from the 2.9.x versions
494 will need to be adapted, as configuration syntax has been very much in flow in
497 -------------------------------------------------------------------------------
499 3.3. What is an "actions" file?
501 Actions files are where various actions that Privoxy might take while
502 processing a certain request, are configured. Typically, you would define a set
503 of default actions that apply to all URLs, then add exceptions to these
504 defaults where needed.
506 Actions can be defined on a URL pattern basis, i.e. for single URLs, whole web
507 sites, groups or parts thereof etc. Actions can also be grouped together and
508 then applied to requests matching one or more patterns. There are many possible
509 actions that might apply to any given site. As an example, if you are blocking
510 cookies as one of your default actions, but need to accept cookies from a given
511 site, you would need to define an exception for this site in one of your
512 actions files, preferably in user.action.
514 -------------------------------------------------------------------------------
516 3.4. The "actions" concept confuses me. Please list some of these "actions".
518 For a comprehensive discussion of the actions concept, please refer to the
519 actions file chapter in the user manual. It includes a list of all actions and
520 an actions file tutorial to get you started.
522 -------------------------------------------------------------------------------
524 3.5. How are actions files configured? What is the easiest way to do this?
526 Actions files are just text files in a special syntax and can be edited with a
527 text editor. But probably the easiest way is to access Privoxy's user interface
528 with your web browser at http://config.privoxy.org/ (Shortcut: http://p.p/) and
529 then select "View & change the current configuration" from the menu.
531 -------------------------------------------------------------------------------
533 3.6. There are several different "actions" files. What are the differences?
535 As of Privoxy v2.9.15, three actions files are being included, to be used for
536 different purposes: These are default.action, the "main" actions file which is
537 actively maintained by the Privoxy developers, user.action, where users are
538 encouraged to make their private customizations, and standard.action, which is
539 for internal Privoxy use only. Please see the actions chapter in the user
540 manual for a more detailed explanation.
542 Earlier versions included three different versions of the default.action file.
543 The new scheme allows for greater flexibility of local configuration, and for
544 browser based selection of pre-defined "aggressiveness" levels.
546 -------------------------------------------------------------------------------
548 3.7. How can I make my Yahoo/Hotmail/GMX account work?
550 The default configuration shouldn't impact the usability of any of these
551 services. It will, however, make all cookies temporary, so that your browser
552 will forget your login credentials in between browser sessions. If you would
553 like not to have to log in manually each time you access those websites, simply
554 turn off all cookie handling for them in the user.action file. An example for
555 yahoo might look like:
557 # Allow all cookies for Yahoo login:
559 { -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only }
562 -------------------------------------------------------------------------------
564 3.8. What's the difference between the "Cautious", "Medium" and "Radical"
567 Configuring Privoxy is not entirely trivial. To help you get started, we
568 provide you with three different default action "profiles" in the web based
569 actions file editor at http://config.privoxy.org/show-status. See the User
570 Manual for a list of actions, and how the default profiles are set.
572 Where the defaults are likely to break some sites, exceptions for known popular
573 "problem" sites are included, but in general, the more aggressive your default
574 settings are, the more exceptions you will have to make later. See the User
575 Manual for a more deatiled discussion.
577 It should be noted that the "Radical" profile (formerly known as the "Advanced"
578 profile) is not only more aggressive, but also includes fun and, extreme usage
579 of most of Privoxy's features. Use at your own risk!
581 -------------------------------------------------------------------------------
583 3.9. Why can I change the configuration with a browser? Does that not raise
586 It may seem strange that regular users can edit the config files with their
587 browsers, although the whole /etc/privoxy hierarchy belongs to the user
588 "privoxy", with only 644 permissions.
590 When you use the browser-based editor, Privoxy itself is writing to the config
591 files. Because Privoxy is running as the user "privoxy", it can update the
594 If you run Privoxy for multiple untrusted users (e.g. in a LAN), you will
595 probably want to turn the web-based editor and remote toggle features off by
596 setting "enable-edit-actions 0" and "enable-remote-toggle 0" in the main
599 Note that in the default configuration, only local users (i.e. those on
600 "localhost") can connect to Privoxy, so this is not (normally) a security
603 -------------------------------------------------------------------------------
605 3.10. What is the default.filter file? What is a "filter"?
607 The default.filter file is where filters are defined, which can be used to
608 modify or remove, web page content on the fly. Filters apply to anything in the
609 page source, including HTML tags, and JavaScript. Regular expressions are used
610 to accomplish this. There are a number of pre-defined filters to deal with
611 common annoyances. The filters are only defined here, to invoke them, you need
612 to use the filter action in one of the actions files. Filtering is
613 automatically disabled for inappropriate MIME types.
615 If you are familiar with regular expressions, and HTML, you can look at the
616 provided default.filter with a text editor and define your own filters. This is
617 potentially a very powerful feature, but requires some expertise in both
618 regular expressions and HTML/HTTP.
620 Presently, there is no GUI editor option for this part of the configuration,
621 but you can disable/enable the various pre-defined filters of the included
622 default.filter file with the web-based actions file editor.
624 -------------------------------------------------------------------------------
626 3.11. How can I set up Privoxy to act as a proxy for my LAN?
628 By default, Privoxy only responds to requests from 127.0.0.1 (localhost). To
629 have it act as a server for a network, this needs to be changed in the main
630 configuration file. Look for the listen-address option, which may be commented
631 out with a "#" symbol. Make sure it is uncommented, and assign it the address
632 of the LAN gateway interface, and port number to use. Assuming your LAN address
633 is 192.168.1.1 and you wish to run Privoxy on port 8118, this line should look
636 listen-address 192.168.1.1:8118
638 Save the file, and restart Privoxy. Configure all browsers on the network then
639 to use this address and port number.
641 Alternately, you can have Privoxy listen on all available interfaces:
645 And then use Privoxy's permit-access feature to limit connections. A firewall
646 in this situation is recommended as well.
648 The above steps should be the same for any TCP network, regardless of operating
651 If you run Privoxy on a LAN with untrusted users, we recommend that you
652 double-check the access control and security options!
654 -------------------------------------------------------------------------------
656 3.12. Instead of ads, now I get a checkerboard pattern. I don't want to see
659 The replacement for blocked images can be controlled with the set-image-blocker
660 action. You have the choice of a checkerboard pattern, a transparent 1x1 GIF
661 image (aka "blank"), or a redirect to a custom image of your choice. Note that
662 this choice only has effect for images which are blocked as images, i.e. whose
663 URLs match both a handle-as-image and block action.
665 If you want to see nothing, then change the set-image-blocker action to
666 "blank". This can be done by editing the default.action file, or trough the
667 web-based actions file editor.
669 -------------------------------------------------------------------------------
671 3.13. Why would anybody want to see a checkerboard pattern?
673 Remember that telling which image is an ad and which isn't, is mostly
674 guesswork. While we hope that the standard configuration is rather smart, it
675 can and will make errors. The checkerboard image is visually decent, but it
676 shows you that and where images were blocked, which can be very helpful in case
677 some navigation aid or otherwise innocent image was erraneously blocked. Some
678 people might also enjoy seeing how many banners they don't have to see..
680 -------------------------------------------------------------------------------
682 3.14. I see some images being replaced by a text instead of the checkerboard
683 image. Why and how do I get rid of this?
685 This happens when the banners are not embedded in the HTML code of the page
686 itself, but in separate HTML (sub)documents that are loaded into (i)frames or
687 (i)layers, and these external HTML documents are blocked. Being non-images they
688 get replaced by a substitute HTML page rather than a substitute image, which
689 wouldn't work out technically, since the browser expects and accepts only HTML
690 when it has requested an HTML document.
692 The substitute page adapts to the available space and shows itself as a
693 miniature two-liner if loaded into small frames, or full-blown with a large red
694 "BLOCKED" banner if space allows.
696 If you prefer the banners to be blocked by images, you must see to it that the
697 HTML documents in which they are embedded are not blocked. Clicking the "See
698 why" link offered in the substitute page will show you which rule blocked the
699 page. After changing the rule and un-blocking the HTML documents, the browser
700 will try to load the actual banner images and the usual image blocking will
701 (hopefully!) kick in.
703 -------------------------------------------------------------------------------
705 3.15. Can Privoxy run as a service on Win2K/NT?
707 Yes, it can run as a system service using srvany.exe. See the discussion at
708 http://sourceforge.net/tracker/?func=detail&atid=361118&aid=485617&group_id=
709 11118, for details, and a sample configuration.
711 Version 3.0.1 fixes the problem where the icon and menu where not available in
712 the taskbar for this usage.
714 -------------------------------------------------------------------------------
716 3.16. How can I make Privoxy work with other proxies like Squid?
718 This can be done and is often useful to combine the benefits of Privoxy with
719 those of a caching proxy. See the forwarding chapter in the user manual which
720 describes how to do this.
722 -------------------------------------------------------------------------------
724 3.17. Can I just set Privoxy to use port 80 and thus avoid individual browser
727 No, its more complicated than that. This only works with special kinds of
728 proxies known as "transparent" proxies (see below).
730 -------------------------------------------------------------------------------
732 3.18. Can Privoxy run as a "transparent" proxy?
734 No, Privoxy currently does not have this ability, though it is planned for a
735 future release. Transparent proxies require special handling of the request
736 headers beyond what Privoxy is now capable of.
738 Chaining Privoxy behind another proxy that has this ability should work though.
739 See the forwarding chapter in the user manual. As a transparent proxy to be
740 used for chaining we recommend Transproxy (http://www.transproxy.nlc.net.au/).
742 -------------------------------------------------------------------------------
744 3.19. How can I configure Privoxy for use with Outlook Express?
746 Outlook Express uses Internet Explorer components to both render HTML, and
747 fetch any HTTP requests that may be embedded in an HTML email. So however you
748 have Privoxy configured to work with IE, this configuration should
749 automatically be shared.
751 -------------------------------------------------------------------------------
753 3.20. How can I have separate rules just for HTML mail?
755 The short answer is, you can't. Privoxy has no way of knowing which particular
756 application makes a request, so there is no way to distinguish between web
757 pages and HTML mail. Privoxy just blindly proxies all requests. In the case of
758 Outlook Express (see above), OE uses IE anyway, and there is no way for Privoxy
759 to ever be able to distinguish between them (nor could any other proxy type
760 application for that matter).
762 For a good discussion of some of the issues involved (including privacy and
763 security issues), see http://sourceforge.net/tracker/?func=detail&atid=211118&
764 aid=629518&group_id=11118.
766 -------------------------------------------------------------------------------
768 3.21. How can I allow permanent cookies for my trusted sites?
770 There are several actions that relate to cookies. The default behavior is to
771 allow only "session cookies", which means the cookies only last for the current
772 browser session. This eliminates most kinds of abuse related to cookies. But
773 there may be cases where we want cookies to last.
775 To disable all cookie actions, so that cookies are allowed unrestricted, both
776 in and out, for example.com:
778 { -crunch-incoming-cookies -crunch-outgoing-cookies -session-cookies-only -filter{content-cookies} }
781 Place the above in user.action. Note some of these may be off by default
782 anyway, so this might be redundant, but there is no harm being explicit in what
783 you want to happen. user.action includes an alias for this situation, called
786 -------------------------------------------------------------------------------
790 4.1. How much does Privoxy slow my browsing down? This has to add extra time to
793 It should not slow you down any in real terms, and may actually help speed
794 things up since ads, banners and other junk are not being displayed. The actual
795 processing time required by Privoxy itself for each page, is relatively small
796 in the overall scheme of things, and happens very quickly. This is typically
797 more than offset by time saved not downloading and rendering ad images.
799 "Filtering" content via the filter or deanimate-gifs actions may cause a
800 perceived slowdown, since the entire document needs to be buffered before
801 displaying. See below.
803 -------------------------------------------------------------------------------
805 4.2. I noticed considerable delays in page requests compared to the old
806 Junkbuster. What's wrong?
808 If you use any filter action, such as filtering banners by size, web-bugs etc,
809 or the deanimate-gifs action, the entire document must be loaded into memory in
810 order for the filtering mechanism to work, and nothing is sent to the browser
813 The loading time does not really change in real numbers, but the feeling is
814 different, because most browsers are able to start rendering incomplete
815 content, giving the user a feeling of "it works". This effect is especially
816 noticeable on slow dialup connections.
818 Filtering is automatically disabled for inappropriate MIME types.
820 -------------------------------------------------------------------------------
822 4.3. What are "http://config.privoxy.org/" and "http://p.p/"?
824 http://config.privoxy.org/ is the address of Privoxy's built-in user interface,
825 and http://p.p/ is a shortcut for it.
827 Since Privoxy sits between your web browser and the Internet, it can simply
828 intercept requests for these addresses and answer them with its built-in "web
831 This also makes for a good test for your browser configuration: If entering the
832 URL http://config.privoxy.org/ takes you to a page saying "This is Privoxy
833 ...", everything is OK. If you get a page saying "Privoxy is not working"
834 instead, then your browser didn't use Privoxy for the request, hence it could
835 not be intercepted, and you have accessed the real web site at
838 With recent versions of Privoxy (version 2.9.x and later), the user interface
839 features information on the run time status, the configuration, and even a
840 built-in editor for the actions files.
842 Note that the built-in URLs from earlier versions of Junkbuster / Privoxy,
843 http://example.com/show-proxy-args and http://i.j.b/, are no longer supported.
844 If you still use such an old version, you should really consider upgrading to
847 -------------------------------------------------------------------------------
849 4.4. Do you still maintain the blocklists?
851 No. The patterns for blocking now reside (among other things) in the actions
852 files, which are actively maintained instead. See next question ...
854 -------------------------------------------------------------------------------
856 4.5. How can I submit new ads?
858 Yes, absolutely! Please see the Contact section for how to do that. Please note
859 that you (technically) need the latest Privoxy version for this to work.
861 -------------------------------------------------------------------------------
863 4.6. How can I hide my IP address?
865 If you run both the browser and the proxy locally, you cannot hide your IP
866 address with Privoxy or any other software. The server needs to know your IP
867 address to send the answers back to you.
869 Fortunately there are many publicly usable anonymous proxies out there, which
870 solve the problem by providing a further level of indirection between you and
871 the web server, shared by many people, and thus letting your requests "drown"
872 in white noise of unrelated requests as far as user tracking is concerned.
874 Most of them will, however, log your IP address and make it available to the
875 authorities in case you abuse that anonymity for criminal purposes. In fact you
876 can't even rule out that some of them only exist to *collect* information on
877 (those suspicious) people with a more than average preference for privacy.
879 You can find a list of anonymous public proxies at multiproxy.org and many more
880 through Google. A particularly interesting project is the JAP service offered
881 by the Technical University of Dresden (http://anon.inf.tu-dresden.de/
884 There is, however, even in the single-machine case the possibility to make the
885 server believe that your machine is in fact a shared proxy serving a whole big
886 LAN, and we are looking into that.
888 -------------------------------------------------------------------------------
890 4.7. Can Privoxy guarantee I am anonymous?
892 No. Your chances of remaining anonymous are greatly improved, but unless you
893 are an expert on Internet security it would be safest to assume that everything
894 you do on the Web can be traced back to you.
896 Privoxy can remove various information about you, and allows you more freedom
897 to decide which sites you can trust, and what details you want to reveal. But
898 it's still possible that web sites can find out who you are. Here's one way
901 A few browsers disclose the user's email address in certain situations, such as
902 when transferring a file by FTP. Privoxy does not filter FTP. If you need this
903 feature, or are concerned about the mail handler of your browser disclosing
904 your email address, you might consider products such as NSClean.
906 Browsers available only as binaries could use non-standard headers to give out
907 any information they can have access to: see the manufacturer's license
908 agreement. It's impossible to anticipate and prevent every breach of privacy
909 that might occur. The professionally paranoid prefer browsers available as
910 source code, because anticipating their behavior is easier. Trust the source,
913 -------------------------------------------------------------------------------
915 4.8. Might some things break because header information or content is being
918 Definitely. More and more sites use HTTP header content to decide what to
919 display and how to display it. There is many ways that this can be handled, so
920 having hard and fast rules, is tricky.
922 "User-Agent" in particular is often used in this way to identify the browser,
923 and adjust content accordingly. Changing this now (at least not further than
924 removing the OS information) is not recommended, since so many sites do look
925 for it. You may get undesirable results by changing this.
927 For instance, different browsers use different encodings of Russian and Czech
928 characters, certain web servers convert pages on-the-fly according to the User
929 Agent header. Giving a "User Agent" with the wrong operating system or browser
930 manufacturer causes some sites in these languages to be garbled; Surfers to
931 Eastern European sites should change it to something closer. And then some page
932 access counters work by looking at the "Referer" header; they may fail or break
933 if unavailable. The weather maps of Intellicast have been blocked by their
934 server when no "Referer" or cookie is provided, is another example. (But you
935 can forge both headers without giving information away). There are many other
936 ways things can go wrong when trying to fool a web server.
938 Similar thoughts apply to modifying JavaScript, and, to a lesser degree, HTML
941 If you have problems with a site, you will have to adjust your configuration
942 accordingly. Cookies are probably the most likely adjustment that may be
943 required, but by no means the only one.
945 -------------------------------------------------------------------------------
947 4.9. Can Privoxy act as a "caching" proxy to speed up web browsing?
949 No, it does not have this ability at all. You want something like Squid for
950 this. And, yes, before you ask, Privoxy can co-exist with other kinds of
951 proxies like Squid. See the forwarding chapter in the user manual for details.
953 -------------------------------------------------------------------------------
955 4.10. What about as a firewall? Can Privoxy protect me?
957 Not in the way you mean, or in the way a true firewall can. Privoxy can help
958 protect your privacy, but not protect you from intrusion attempts. It is, of
959 course, perfectly possible and recommended to use both.
961 -------------------------------------------------------------------------------
963 4.11. I have large empty spaces / a checkerboard pattern now where ads used to
966 It would be technically possible eliminate the banners in a way that frees
967 their screen estate in many cases, by doing all banner blocking with filters,
968 i.e. eliminating the whole image references from the HTML pages instead of
969 letting them stay in, and blocking the resulting requests for the banners
972 But this would consume considerable CPU resources, would likely destroy the
973 layout of many web pages which rely on the banners consuming a certain amount
974 of screen space, and would fail in other cases, where the screen space is
975 reserved e.g. by tables anyway. Also, making the banners disappear without a
976 visual trace complicates troubleshooting.
978 So we won't support this in the default configuration, but you can of course
979 define appropriate filters yourself.
981 -------------------------------------------------------------------------------
983 4.12. How can Privoxy filter Secure (HTTPS) URLs?
985 Since secure HTTP connections are encrypted SSL sessions between your browser
986 and the secure site, and are meant to be reliably secure, there is little that
987 Privoxy can do but hand the raw gibberish data though from one end to the other
990 The only exception to this is blocking by host patterns, as the client needs to
991 tell Privoxy the name of the remote server, so that Privoxy can establish the
992 connection. If that name matches a host-only pattern, the connection will be
995 As far as ad blocking is concerned, this is less of a restriction than it may
996 seem, since ad sources are often identifiable by the host name, and often the
997 banners to be placed in an encrypted page come unencrypted nonetheless for
998 efficiency reasons, which exposes them to the full power of Privoxy's ad
1001 "Content cookies" (those that are embedded in the actual HTML or JS page
1002 content, see filter{content-cookies}), in an SSL transaction will be impossible
1003 to block under these conditions. Fortunately, this does not seem to be a very
1004 common scenario since most cookies come by traditional means.
1006 -------------------------------------------------------------------------------
1008 4.13. Privoxy runs as a "server". How secure is it? Do I need to take any
1009 special precautions?
1011 There are no known exploits that might affect Privoxy. On Unix-like systems,
1012 Privoxy can run as a non-privileged user, which is how we recommend it be run.
1013 Also, by default Privoxy only listens to requests from "localhost" only. The
1014 server aspect of Privoxy is not itself directly exposed to the Internet in this
1015 configuration. If you want to have Privoxy serve as a LAN proxy, this will have
1016 to be opened up to allow for LAN requests. In this case, we'd recommend you
1017 specify only the LAN gateway address, e.g. 192.168.1.1, in the main Privoxy
1018 configuration file and check all access control and security options. All LAN
1019 hosts can then use this as their proxy address in the browser proxy
1020 configuration, but Privoxy will not listen on any external interfaces. ACLs can
1021 be defined in addition, and using a firewall is always good too. Better safe
1024 -------------------------------------------------------------------------------
1026 4.14. How can I temporarily disable Privoxy?
1028 The easiest way is to access Privoxy with your browser by using the remote
1029 toggle URL: http://config.privoxy.org/toggle. See the Bookmarklets section of
1030 the User Manual for an easy way to access this feature.
1032 -------------------------------------------------------------------------------
1034 4.15. When "disabled" is Privoxy totally out of the picture?
1036 No, this just means all filtering and actions are disabled. Privoxy is still
1037 acting as a proxy, but just not doing any of the things that Privoxy would
1038 normally be expected to do. It is still a "middle-man" in the interaction
1039 between your browser and web sites.
1041 -------------------------------------------------------------------------------
1043 4.16. My logs show Privoxy "crunches" ads, but also its own CGI pages. What is
1046 A "crunch" simply means Privoxy intercepted something, nothing more. Often this
1047 is indeed ads or banners, but Privoxy uses the same mechanism for trapping
1048 requests for its own internal pages. For instance, a request for Privoxy's
1049 configuration page at: http://config.privoxy.org, is intercepted (i.e. it does
1050 not go out to the 'net), and the familiar CGI configuration is returned to the
1051 browser, and the log consequently will show a "crunch".
1053 -------------------------------------------------------------------------------
1055 4.17. Can Privoxy effect files that I download from a webserver? FTP server?
1057 From the webserver's perspective, there is no difference between viewing a
1058 document (i.e. a page), and downloading a file. The same is true of Privoxy. If
1059 there is a match for a block pattern, it will still be blocked, and of course
1060 this is obvious. Filtering is potentially more of a concern since the results
1061 are not always so obvious.
1063 Privoxy knows the differences in files according to the "Document Type" as
1064 reported by the webserver. If this is reported accurately (e.g. "application/
1065 zip" for a zip archive), then Privoxy knows to ignore these where appropriate.
1066 It is possible, however, that documents that are of an unknown type (generally
1067 assumed to be "text/plain") will be filtered, as will those that might be
1068 incorrectly reported by the webserver. If such a file is a downloaded file that
1069 is intended to be saved to disk, then any content that might have been altered
1070 by filtering, will be saved too, for these (probably very rare) cases.
1072 Privoxy does not do FTP at all, only HTTP protocols.
1074 -------------------------------------------------------------------------------
1076 4.18. Where can I find more information about Privoxy and related issues?
1078 Other references and sites of interest to Privoxy users:
1080 http://www.privoxy.org/, the Privoxy Home page.
1082 http://www.privoxy.org/faq/, the Privoxy FAQ.
1084 http://sourceforge.net/projects/ijbswa/, the Project Page for Privoxy on
1087 http://config.privoxy.org/, the web-based user interface. Privoxy must be
1088 running for this to work. Shortcut: http://p.p/
1090 http://www.privoxy.org/actions/, to submit "misses" to the developers.
1092 http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/ijbswa/contrib/, cool and fun
1093 ideas from Privoxy users.
1095 http://www.junkbusters.com/ht/en/cookies.html, an explanation how cookies are
1096 used to track web users.
1098 http://www.junkbusters.com/ijb.html, the original Internet Junkbuster.
1100 http://www.waldherr.org/junkbuster/, Stefan Waldherr's version of Junkbuster,
1101 from which Privoxy was derived.
1103 http://privacy.net/analyze/, a useful site to check what information about you
1104 is leaked while you browse the web.
1106 http://www.squid-cache.org/, a very popular caching proxy, which is often used
1107 together with Privoxy.
1109 http://www.privoxy.org/developer-manual/, the Privoxy developer manual.
1111 -------------------------------------------------------------------------------
1113 4.19. I've noticed that Privoxy changes "Microsoft" to "MicroSuck"! Why are you
1114 manipulating my browsing?
1116 We're not. The text substitutions that you are seeing are disabled in the
1117 default configuration as shipped. You have either manually activated the "fun"
1118 filter which is clearly labeled "Text replacements for subversive browsing fun!
1119 " or you have implicitly activated it by choosing the "Radical" profile in the
1120 web-based editor (formerly known as the Advanced profile).
1122 -------------------------------------------------------------------------------
1126 5.1. I just upgraded and am getting "connection refused" with every web page?
1128 Either Privoxy is not running, or your browser is configured for a different
1129 port than what Privoxy is using.
1131 The old Privoxy (and also Junkbuster) used port 8000 by default. This has been
1132 changed to port 8118 now, due to a conflict with NAS (Network Audio Service),
1133 which uses port 8000. If you haven't, you need to change your browser to the
1134 new port number, or alternately change the listen-address option in Privoxy's
1135 main configuration file.
1137 -------------------------------------------------------------------------------
1139 5.2. I just added a new rule, but the steenkin ad is still getting through.
1142 If the ad had been displayed before you added its URL, it will probably be held
1143 in the browser's cache for some time, so it will be displayed without the need
1144 for any request to the server, and Privoxy will not be in the picture. The best
1145 thing to do is try flushing the browser's caches. And then try again.
1147 If this doesn't help, you probably have an error in the rule you applied. Try
1148 pasting the full URL of the offending ad into http://config.privoxy.org/
1149 show-url-info and see if it really matches your new rule.
1151 -------------------------------------------------------------------------------
1153 5.3. One of my favorite sites does not work with Privoxy. What can I do?
1155 First verify that it is indeed a Privoxy problem, by toggling off Privoxy
1156 through http://config.privoxy.org/toggle, and then shift-reloading the problem
1157 page (i.e. holding down the shift key while clicking reload. Alternatively,
1158 flush your browser's disk and memory caches).
1160 If still a problem, go to http://config.privoxy.org/show-url-info and paste the
1161 full URL of the page in question into the prompt. See which actions are being
1162 applied to the URL, and which matches in which actions files are responsible
1163 for that. Now, armed with this information, go to http://config.privoxy.org/
1164 show-status and select the appropriate actions files for editing.
1166 You can now either look for a section which disables the actions that you
1167 suspect to cause the problem and add a pattern for your site there, or make up
1168 a completely new section for your site. In any case, the recommended way is to
1169 disable only the prime suspect, reload the problem page, and only if the
1170 problem persists, disable more and more actions until you have identified the
1171 culprit. You may or may not want to turn the other actions on again. Remember
1172 to flush your browser's caches in between any such changes!
1174 Alternately, if you are comfortable with a text editor, you can accomplish the
1175 same thing by editing the appropriate actions file. Probably the easiest way to
1176 deal with such problems when editing by hand is to add your site to a { fragile
1177 } section in user.action, which is an alias that turns off most "dangerous"
1178 actions, but is also likely to turn off more actions then needed, and thus
1179 lower your privacy and protection more than necessary,
1181 Troubleshooting actions is discussed in more detail in the user-manual appendix
1182 . There is also an actions tutorial.
1184 -------------------------------------------------------------------------------
1186 5.4. After installing Privoxy, I have to log in every time I start IE. What
1189 This is a quirk that effects the installation of Privoxy, in conjunction with
1190 Internet Explorer and Internet Connection Sharing on Windows 2000 and Windows
1191 XP. The symptoms may appear to be corrupted or invalid DUN settings, or
1194 When setting up an NT based Windows system with Privoxy you may find that
1195 things do not seem to be doing what you expect. When you set your system up you
1196 will probably have set up Internet Connection Sharing (ICS) with Dial up
1197 Networking (DUN) when logged in with administrator privileges. You will
1198 probably have made this DUN connection available to other accounts that you may
1199 have set-up on your system. E.g. Mum or Dad sets up the system and makes
1200 accounts suitably configured for the kids.
1202 When setting up Privoxy in this environment you will have to alter the proxy
1203 set-up of Internet Explorer (IE) for the specific DUN connection on which you
1204 wish to use Privoxy. When you do this the ICS DUN set-up becomes user specific.
1205 In this instance you will see no difference if you change the DUN connection
1206 under the account used to set-up the connection. However when you do this from
1207 another user you will notice that the DUN connection changes to make available
1208 to "Me only". You will also find that you have to store the password under each
1211 The reason for this is that each user's set-up for IE is user specific. Each
1212 set-up DUN connection and each LAN connection in IE store the settings for each
1213 user individually. As such this enforces individual configurations rather than
1214 common ones. Hence the first time you use a DUN connection after re-booting
1215 your system it may not perform as you expect, and prompt you for the password.
1216 Just set and save the password again and all should be OK.
1218 [Thanks to Ray Griffith for this submission.]
1220 -------------------------------------------------------------------------------
1222 5.5. I cannot connect to any FTP sites. Privoxy seems to be blocking me.
1224 Privoxy cannot act as a proxy for FTP traffic, so do not configure your browser
1225 to use Privoxy as an FTP proxy. The same is true for any protocol other than
1228 Most browsers understand FTP as well as HTTP. If you connect to a site, with a
1229 URL like ftp://ftp.example.com, your browser is making an FTP connection, and
1230 not a HTTP connection. So while your browser may speak FTP, Privoxy does not,
1231 and cannot proxy such traffic.
1233 -------------------------------------------------------------------------------
1235 5.6. In Mac OSX, I can't configure Microsoft Internet Explorer to use Privoxy
1238 Microsoft Internet Explorer (in versions like 5.1) respects system-wide network
1239 settings. In order to change the HTTP proxy, open System Preferences, and click
1240 on the Network icon. In the settings pane that comes up, click on the Proxies
1241 tab. Ensure the "Web Proxy (HTTP)" checkbox is checked and enter 127.0.0.1 in
1242 the entry field. Enter 8118 in the Port field. The next time you start IE, it
1243 should reflect these values.
1245 -------------------------------------------------------------------------------
1247 5.7. In Mac OSX, I dragged the Privoxy folder to the trash in order to
1248 uninstall it. Now the finder tells me I don't have sufficient privileges to
1251 Just dragging the Privoxy folder to the trash is not enough to delete it.
1252 Privoxy supplies an uninstall.command file that takes care of these details.
1253 Open the trash, drag the uninstall.command file out of the trash and
1254 double-click on it. You will be prompted for confirmation and the
1255 administration password.
1257 The trash may still appear full after this command; emptying the trash from the
1258 desktop should make it appear empty again.
1260 -------------------------------------------------------------------------------
1262 5.8. I get a completely blank page at one site. "View Source" shows only:
1263 <html><body></body></html>. Without Privoxy the page loads fine.
1265 Chances are that the site suffers from a bug in PHP, which results in empty
1266 pages being sent if the client explicitly requests an uncompressed page, like
1267 Privoxy does. This bug has been fixed in PHP 4.2.3.
1269 To find out if this is in fact the source of the problem, try adding the site
1270 to a -prevent-compression section in user.action:
1272 # Make exceptions for ill-behaved sites:
1274 {-prevent-compression}
1277 If that works, you may also want to report the problem to the site's
1278 webmasters, telling them to use zlib.output_compression instead of ob_gzhandler
1279 in their PHP applications (workaround) or upgrade to PHP 4.2.3 or later (fix).
1281 -------------------------------------------------------------------------------
1283 5.9. Why am I getting a 503 Error (WSAECONNREFUSED) on every page?
1285 More than likely this is a problem with the network stack. ZoneAlarm has been
1286 reported to cause this symptom -- even if not running. The solution is to
1287 either fight the ZA configuration, or uninstall ZoneAlarm, and then find
1288 something better behaved in its place. Other firewall type products may cause
1289 similar type problems if not configured correctly.
1291 -------------------------------------------------------------------------------
1293 6. Contacting the developers, Bug Reporting and Feature Requests
1295 We value your feedback. In fact, we rely on it to improve Privoxy and its
1296 configuration. However, please note the following hints, so we can provide you
1297 with the best support:
1299 -------------------------------------------------------------------------------
1303 For casual users, our support forum at SourceForge is probably best suited:
1304 http://sourceforge.net/tracker/?group_id=11118&atid=211118
1306 All users are of course welcome to discuss their issues on the users mailing
1307 list, where the developers also hang around.
1309 -------------------------------------------------------------------------------
1313 Please report all bugs only through our bug tracker: http://sourceforge.net/
1314 tracker/?group_id=11118&atid=111118.
1316 Before doing so, please make sure that the bug has not already been submitted
1317 and observe the additional hints at the top of the submit form.
1319 Please try to verify that it is a Privoxy bug, and not a browser or site bug
1320 first. If unsure, try toggling off Privoxy, and see if the problem persists.
1321 The appendix of the user manual also has helpful information on action
1322 debugging. If you are using your own custom configuration, please try the stock
1323 configs to see if the problem is configuration related.
1325 If not using the latest version, chances are that the bug has been found and
1326 fixed in the meantime. We would appreciate if you could take the time to
1327 upgrade to the latest version (or even the latest CVS snapshot) and verify your
1328 bug, but this is not required for reporting.
1330 -------------------------------------------------------------------------------
1332 6.3. Request New Features
1334 You are welcome to submit ideas on new features or other proposals for
1335 improvement through our feature request tracker at http://sourceforge.net/
1336 tracker/?atid=361118&group_id=11118.
1338 -------------------------------------------------------------------------------
1340 6.4. Report Ads or Other Actions-Related Problems
1342 Please send feedback on ads that slipped through, innocent images that were
1343 blocked, and any other problems relating to the default.action file through our
1344 actions feedback mechanism located at http://www.privoxy.org/actions/. On this
1345 page, you will also find a bookmark which will take you back there from any
1346 troubled site and even pre-fill the form!
1348 New, improved default.action files will occasionally be made available based on
1349 your feedback. These will be announced on the ijbswa-announce list and
1350 available from our the files section of our project page.
1352 -------------------------------------------------------------------------------
1356 For any other issues, feel free to use the mailing lists. Technically
1357 interested users and people who wish to contribute to the project are also
1358 welcome on the developers list! You can find an overview of all Privoxy-related
1359 mailing lists, including list archives, at: http://sourceforge.net/mail/?
1362 -------------------------------------------------------------------------------
1364 7. Privoxy Copyright, License and History
1366 Copyright © 2001, 2002 by Privoxy Developers <developers@privoxy.org>
1368 Some source code is based on code Copyright © 1997 by Anonymous Coders and
1369 Junkbusters, Inc. and licensed under the GNU General Public License.
1371 Portions of this document are "borrowed" from the original Junkbuster (tm) FAQ,
1372 and modified as appropriate for Privoxy.
1374 -------------------------------------------------------------------------------
1378 Privoxy is free software; you can redistribute it and/or modify it under the
1379 terms of the GNU General Public License, version 2, as published by the Free
1380 Software Foundation.
1382 This program is distributed in the hope that it will be useful, but WITHOUT ANY
1383 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
1384 PARTICULAR PURPOSE. See the GNU General Public License for more details, which
1385 is available from the Free Software Foundation, Inc, 59 Temple Place - Suite
1386 330, Boston, MA 02111-1307, USA.
1388 You should have received a copy of the GNU General Public License along with
1389 this program; if not, write to the
1392 Foundation, Inc. 59 Temple Place - Suite 330
1393 Boston, MA 02111-1307
1396 -------------------------------------------------------------------------------
1400 In the beginning, there was the Internet Junkbuster, by Anonymous Coders and
1401 Junkbusters Corporation. It saved many users a lot of pain in the early days of
1402 web advertising and user tracking.
1404 But the web, its protocols and standards, and with it, the techniques for
1405 forcing users to consume ads, give up autonomy over their browsing, and for
1406 spying on them, kept evolving. Unfortunately, the Internet Junkbuster did not.
1407 Version 2.0.2, published in 1998, was (and is) the last official release
1408 available from Junkbusters Corporation. Fortunately, it had been released under
1409 the GNU GPL, which allowed further development by others.
1411 So Stefan Waldherr started maintaining an improved version of the software, to
1412 which eventually a number of people contributed patches. It could already
1413 replace banners with a transparent image, and had a first version of pop-up
1414 killing, but it was still very closely based on the original, with all its
1415 limitations, such as the lack of HTTP/1.1 support, flexible per-site
1416 configuration, or content modification. The last release from this effort was
1417 version 2.0.2-10, published in 2000.
1419 Then, some developers picked up the thread, and started turning the software
1420 inside out, upside down, and then reassembled it, adding many new features
1423 The result of this is Privoxy, whose first stable release, 3.0, was released