X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=doc%2Fwebserver%2Ffaq%2Ftrouble.html;h=236c34aeda381cc6ff26d440638384599ecce743;hp=59af117ac4340e5911ccf1b2f05d098d9993a0b1;hb=2da7c5e4fb2bd663ff7118bbabd2f0f4b3ea98dc;hpb=2d6b5d2e894f920d7e376a9dc4fa436a8dbefcec diff --git a/doc/webserver/faq/trouble.html b/doc/webserver/faq/trouble.html index 59af117a..236c34ae 100644 --- a/doc/webserver/faq/trouble.html +++ b/doc/webserver/faq/trouble.html @@ -1,11 +1,11 @@ + Troubleshooting

5.3. One of my favorite sites does not work with Privoxy. +NAME="BADSITE" +>5.4. One of my favorite sites does not work with Privoxy. What can I do?

Privoxy problem, - by disabling Privoxy filtering and blocking. - Go to through http://p.p/ and click on +>http://config.privoxy.org/toggle + (the toggle feature may need to be enabled in the main + config), + and then shift-reloading the problem page (i.e. holding down the shift key + while clicking reload. Alternatively, flush your browser's disk and memory + caches).

If the problem went away, we know we have a configuration related problem. + Now go to http://config.privoxy.org/show-url-info + and paste the full URL of the page in question into the prompt. See which + actions are being applied to the URL, and which matches in which actions + files are responsible for that. It might be helpful also to look at your logs + for this site too, to see what else might be happening (note: logging may need + to be enabled in the main config file). Many sites are + complex and require a number of related pages to help present their content. + Look at what else might be used by the page in question, and what of that + might be required. + Now, armed with this information, go to + http://config.privoxy.org/show-status + and select the appropriate actions files for editing.

You can now either look for a section which disables the actions that + you suspect to cause the problem and add a pattern for your site there, + or make up a completely new section for your site. In any case, the recommended + way is to disable only the prime suspect, reload the problem page, and only + if the problem persists, disable more and more actions until you have + identified the culprit. You may or may not want to turn the other actions + on again. Remember to flush your browser's caches in between any such changes!

Alternately, if you are comfortable with a text editor, you can accomplish + the same thing by editing the appropriate actions file. Probably the easiest + way to deal with such problems when editing by hand is to add your + site to a { fragile } section in user.action, + which is an alias that turns off most "dangerous" + 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, + Troubleshooting: the Anatomy of an Action. + There is also an actions tutorial + with general configuration information and examples.

As a last resort, you can always see if your browser has a setting that will + bypass the proxy setting for selective sites. Modern browsers can do this.

5.5. After installing Privoxy, I have to log in +every time I start IE. What gives?

This is a quirk that effects the installation of + Privoxy, in conjunction with Internet Explorer and + Internet Connection Sharing on Windows 2000 and Windows XP. The symptoms may + appear to be corrupted or invalid DUN settings, or passwords.

When setting up an NT based Windows system with + Privoxy you may find that things do not seem to be + doing what you expect. When you set your system up you will probably have set + up Internet Connection Sharing (ICS) with Dial up Networking (DUN) when + logged in with administrator privileges. You will probably have made this DUN + connection available to other accounts that you may have set-up on your + system. E.g. Mum or Dad sets up the system and makes accounts suitably + configured for the kids.

When setting up Privoxy in this environment you + will have to alter the proxy set-up of Internet Explorer (IE) for the + specific DUN connection on which you wish to use Privoxy. When you do this the ICS DUN set-up + becomes user specific. In this instance you will see no difference if you + change the DUN connection under the account used to set-up the connection. + However when you do this from another user you will notice that the DUN + connection changes to make available to "Me only". You will also find that + you have to store the password under each different user!

The reason for this is that each user's set-up for IE is user specific. Each + set-up DUN connection and each LAN connection in IE store the settings for + each user individually. As such this enforces individual configurations + rather than common ones. Hence the first time you use a DUN connection after + re-booting your system it may not perform as you expect, and prompt you for + the password. Just set and save the password again and all should be OK.

[Thanks to Ray Griffith for this submission.]

5.6. 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 (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 not a HTTP connection. So while your browser may + speak FTP, Privoxy does not, and cannot proxy + such traffic. +

To complicate matters, some systems may have a generic "Toggle Privoxy On or Off", then disable it. Now try that - page again. It's probably a good idea to flush the browser cache as well - with "proxy" + setting, which will 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. +

5.7. In Mac OS X, I can't configure Microsoft Internet Explorer to use + Privoxy as the HTTP proxy.

Microsoft Internet Explorer (in versions like 5.1) respects system-wide + network settings. In order to change the HTTP proxy, open System + Preferences, and click on the Network icon. In the settings pane that + comes up, click on the Proxies tab. Ensure the "Web Proxy (HTTP)" checkbox + is checked and enter 127.0.0.1 in the entry field. + Enter 8118 in the Port field. The next time you start + IE, it should reflect these values. +

5.8. In Mac OS X, I dragged the Privoxy folder to the trash in order to + uninstall it. Now the finder tells me I don't have sufficient privileges to + empty the trash.

Note: This ONLY applies to privoxy 3.0.6 and earlier. +

Just dragging the Privoxy folder to the trash is + not enough to delete it. Privoxy supplies an + uninstall.command file that takes care of + these details. Open the trash, drag the uninstall.command + file out of the trash and double-click on it. You will be prompted for + confirmation and the administration password. +

The trash may still appear full after this command; emptying the trash + from the desktop should make it appear empty again. +

5.9. In Mac OS X Panther (10.3), images often fail to load and/or I + experience random delays in page loading. I'm using + Shift+Reload to flush caches.

localhost
as my browser's proxy setting.

If still a problem, go to We believe this is due to an IPv6-related bug in Mac OS X, but don't fully + understand the issue yet. In any case, changing the proxy setting to + 127.0.0.1 instead of localhost + works around the problem. +

5.10. I get a completely blank page at one site. "Show which actions apply to a URL and - why" from "View Source" + shows only: <html><body></body></html>. Without + Privoxy the page loads fine.

Chances are that the site suffers from a bug in + http://p.p/ and paste - the full URL of the page in question into the prompt. See which actions are - being applied to the URL. Now, armed with this information, go to +>PHP, + which results in empty pages being sent if the client explicitly requests + an uncompressed page, like Privoxy does. + This bug has been fixed in PHP 4.2.3. +

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

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 in their PHP applications (workaround) + or upgrade to PHP 4.2.3 or later (fix). +

5.11. My logs show many "Unable to get my own hostname" lines. +Why?

Privoxy tries to get the hostname of the system + its running on from the IP address of the system interface it is bound to + (from the config file + listen-address setting). If the system cannot supply + this information, Privoxy logs this condition.

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. Make sure whatever name(s) are used for the local system, + that they resolve both ways.

You should also be able to work around the problem with the + hostname option.

5.12. When I try to launch Privoxy, I get an +error message "port 8118 is already in use" (or similar wording). +Why?

Port 8118 is Privoxy's default TCP + "listening" port. Typically this message would mean that there + is already one instance of Privoxy running, and + your system is actually trying to start a second Privoxy on the same port, which will not 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. 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.

5.14. Why are binary files (such as images) corrupted when Privoxy + is used?

This may also be caused by the "demoronizer" filter, + in conjunction with a web server that is misreporting the content type. Binary + files are exempted from 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.

5.15. What is the "demoronizer" and why is it there?

The original demoronizer was a Perl script that cleaned up HTML pages which + were created with certain Microsoft products. MS has used proprietary extensions + to standardized font encodings (ISO 8859-1), which has caused problems for pages + that are viewed with non-Microsoft products (and are expecting to see a + standard set of fonts). The demoronizer corrected these errors so the pages + displayed correctly. Privoxy borrowed from this + script, introducing a filter based on the original demoronizer, which in turn could + correct these errors on the fly.

But this is only needed in some situations, and will cause serious problems in some + other situations.

If you are using Microsoft products, you do not need it. If you need to view + pages with UTF-8 characters (such as Cyrillic or Chinese), then it will + cause corruption of the fonts, and thus should not be on.

On the other hand, if you use non-Microsoft products, and you occasionally + notice weird characters on pages, you might want to try it.

5.16. Why do I keep seeing "View & change the current configuration". Here you should see various sections that have - various "PrivoxyWindowOpen()" in raw source code?

Privoxy features disabled for specific - sites. Most disabled is attempting to disable malicious + Javascript + in this case, with the unsolicited-popups + filter. Privoxy cannot tell very well + "actions" will have a "good" code snippets from "-" (minus - sign) in front of them. Some aliases are used just to disable other actions, - e.g. "bad" code snippets.

If you see this in HTML source, and the page displays without problems, then + this is good, and likely some pop-up window was disabled. If you see this + where it is causing a problem, such as a downloaded program source code file, + then you should set an exception for this site or page such that the + integrity of the page stays in tact by disabling all filtering.

5.17. I am getting too many DNS errors like "shop" and "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 "fragile", and won't necessarily - use a "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 "+" or "socks4a" proxy, the socks + server handles all the DNS. Privoxy would just be + the "-" sign. Add your problem page - URL to one of these sections that looks like it is disabling the feature that - is causing the problem. Rember to flush your browser's caches when making - such changes! As a last resort, try "messenger" which is reporting whatever problem occurred + downstream, and not the root cause of the error.

In any case, versions newer than 3.0.3 include 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 "fragile" which - disables most actions. Now re-try the page. There might be some trial and - error involved. This is discussed in more detail in 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. If you run into this problem + with a recent Privoxy version, please send a problem report.

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. Either way, if you are using a + recent Privoxy version, please report the problem.

5.20. Why do my filters work on some sites but not on others?

It's probably due to compression. It is a common practice for web servers to + send their content "compressed" in order to speed things up, and + then let the browser "uncompress" them. When compiled with zlib support + Privoxy can decompress content before filtering, otherwise you may want to enable +user-manual appendix.

prevent-compression.

Alternately, if you are comfortable with a text editor, you can accomplish - the same thing by editing the appropriate As of Privoxy 3.0.9, zlib support is enabled in the default builds.

5.21. On some HTTPS sites my browser warns me about unauthenticated content, + the URL bar doesn't get highlighted and the lock symbol appears to be broken. + What's going on?

Probably the browser is requesting ads through HTTPS and Privoxy + is blocking the requests. Privoxy's error messages are delivered + unencrypted and while it's obvious for the browser that the HTTPS + request is already blocked by the proxy, some warn about unauthenticated + content anyway.

To work around the problem you can redirect those requests to an invalid + local address instead of blocking them. While the redirects aren't + encrypted either, many browsers don't care. They simply follow the + redirect, fail to reach a server and display an error message instead + of the ad.

To do that, enable logging to figure out which requests get blocked by + Privoxy and add the hosts (no path patterns) to a section like this:

{+redirect{http://127.0.0.1:0/} -block -limit-connect}
+.ivwbox.de:443/

Additionally you have to configure your browser to contact + "127.0.0.1:0" directly (instead of through Privoxy).

To add a proxy exception in Mozilla Firefox + open the "Preferences", click the "Settings" + button located on the "Network" tab in the "Advanced" + section, and add "127.0.0.1:0" in the "No Proxy for:" + field.

5.22. I get selinux error messages. How can I fix this?

Please report the problem to the creator of your selinux policies.

The problem is that some selinux policy writers aren't familiar + with the application they are trying to "secure" and + thus create policies that make no sense.

In Privoxy's case the problem usually + is that the policy only allows outgoing connections for certain + destination ports (e.g. 80 and 443). While this may cover the + standard ports, websites occasionally use other ports as well. + This isn't a security problem and therefore Privoxy's + default configuration doesn't block these requests.

If you really want to block these ports (and don't be able + to load websites that don't use standard ports), you should + configure Privoxy to block these ports as well, so it doesn't + trigger the selinux warnings.

5.23. I compiled Privoxy with Gentoo's portage and it appears to be very slow. Why?

Probably you unintentionally compiled Privoxy without threading support + in which case requests have to be serialized and only one can be served + at the same time.

Check your "USE" flags and make sure they include + "threads". If they don't, add the flag and rebuild Privoxy.

If you compiled Privoxy with threading support (on POSIX-based systems), + the "Conditional #defines" section on http://config.privoxy.org/show-status + will list "FEATURE_PTHREAD" as "actions" file.

"enabled".