Issues related to plugins: Difference between revisions

From MozillaZine Knowledge Base
Jump to navigationJump to search
m (→‎Related bug reports: Marked bug reports as fixed)
Line 93: Line 93:
*[http://support.mozilla.com/en-US/kb/Troubleshooting+plugins Troubleshooting plugins (Firefox Support)]
*[http://support.mozilla.com/en-US/kb/Troubleshooting+plugins Troubleshooting plugins (Firefox Support)]
===Related bug reports===
===Related bug reports===
*[https://bugzilla.mozilla.org/show_bug.cgi?id=339056 Bug 339056 – provide mechanism to allow users to list, enable, disable plugins in primary UI]
*[https://bugzilla.mozilla.org/show_bug.cgi?id=339056 Bug 339056 – provide mechanism to allow users to list, enable, disable plugins in primary UI (fixed)]
*[https://bugzilla.mozilla.org/show_bug.cgi?id=382367 Bug 382367 – Add support for enabling and disabling individual plugins]
*[https://bugzilla.mozilla.org/show_bug.cgi?id=382367 Bug 382367 – Add support for enabling and disabling individual plugins (fixed)]





Revision as of 14:11, 8 December 2008

This article explains how to identify and disable installed plugins in Firefox and Mozilla Suite/SeaMonkey.

If you suspect that a problem with your Mozilla browser issue is related to a plugin, you should perform the standard diagnostic steps first, to rule out problems caused by other issues such as problematic extensions or profile issues. If you already know that your issue is related to a specific plugin because of problems with certain web content or because you received an error message identifying the plugin, look through the articles in the Category:Plugins for a solution.

Background

Mozilla browsers often need plugins for web content that cannot be handled internally, such as Java applets, Flash movies and embedded audio and video. (Note that JavaScript is often required for Flash to run correctly. Note also that JavaScript is neither a plugin nor Java.) Mozilla browsers find installed plugins by searching in different locations [1].

On Windows, common plugins are located via plugin scanning; other plugins are detected in the Mozilla browser installation directory "plugins" folder (e.g., in Firefox, C:\Program Files\Mozilla Firefox\plugins). If different plugins for the same MIME type are found in multiple locations, the plugin found in the installation directory plugins folder will normally be used.

Starting in Firefox 3, and in SeaMonkey 2 (not yet released), you can view, disable, and enable plugins from the "Tools" menu, via "Add-ons (Add-on Manager) -> Plugins". To disable a specific plugin in Firefox 3 or SeaMonkey 2, you can open the Add-ons window, select the plugin you wish to disable, and click the Disable button, as shown in this SeaMonkey 2 screenshot. You should use this new feature instead of disabling plugins by manually renaming or removing the associated plugin files as described below. [2]

Also starting in Firefox 3, plugin versions that are known to cause crashes or other problems are added to the Add-ons Blocklist and are automatically disabled. [3] For example, the older Quicktime plugin version 7.1.x for Windows has been blocklisted and is disabled automatically in Firefox 3. [4]

Since older versions of plugins may have bugs that are fixed in newer versions, you should keep your plugins updated, as a general rule.

You can diagnose problems you suspect are plugin-related by removing or disabling the plugin. If the problem goes away, it was caused by the plugin. Keep in mind that if you disable or remove a plugin, embedded web content handled by that plugin will be missing and you may receive a "missing plugin" alert.

Identifying installed plugins

You can see a list of detected plugins by entering about:plugins in the Location Bar (address bar). The installed plugins list will include the file name and a description of the plugin along with the associated MIME types handled by each plugin. On Windows, all Mozilla browser plugin file names begin with np and end with .dll. (Note that some plugins like Quicktime or Java include multiple plugin files, each with a different file name.) If you set the plugin.expose_full_path preference to true in about:config, you will be able to see the full path to each plugin file in the about:plugins list, instead of just the file name.

Mozilla Default Plug-in

On Windows, Mozilla browser installations include the Mozilla Default Plug-in "npnul32.dll", located in the browser installation directory "plugins" folder. Mozilla Suite and SeaMonkey need this plugin for the "click here to get the plugin" alert on web pages that need plugins that are missing. Firefox does not require this plugin as the "Additional plugins are required..." yellow message bar will display without it.

Disabling plugins found in the plugins folder

Applies to Windows systems

You can temporarily disable some of the plugins that your Mozilla browser is detecting by renaming or removing the associated files from the installation directory "plugins" folder, as follows:

Firefox

  1. Completely exit Firefox.
  2. Open the Firefox "plugins" folder (e.g., C:\Program Files\Mozilla Firefox\plugins).
  3. Do one of the following:
    • Rename each "np*.dll" file by adding an "X" before the name, or
    • Remove all of the files in the plugins folder to a backup location.
  4. Restart Firefox.

If the problem persists, you should check the about:plugins list again to see what plugins are still being detected via plugin scanning. Additionally, some programs that include browser plugins such as Quicktime may copy back any removed plugin files to the browser plugins folder.

If the problem goes away, it was caused by one of the disabled plugins. You can try to identify the problematic plugin and restore the other plugin files or you can simply reinstall any missing plugins as needed.

Mozilla Suite or SeaMonkey

Follow the same procedure given above, except do not rename or remove the Mozilla Default Plug-in "npnul32.dll" from the Mozilla Suite or SeaMonkey installation directory "plugins" folder, since this file is needed for missing plugin alerts (see above).

Disabling the automatic plugin scan

Applies to Windows systems

On Windows systems, Mozilla browsers will scan for common plugins in other locations, even if the browser plugins folder is empty. You can prevent the automatic scan for for common plugins such as Windows Media Player or Real Player by modifying the related preference settings. For detailed instructions, see this article. Note that some plugins that are detected via plugin scanning such as Java or Adobe Reader can be disabled by other methods, described below.

Other methods of disabling plugins

  • You can disable Java in your browser settings to prevent Java applets from running. This will help determine whether the Java plugin is causing your issues such as a persistent browser process after exiting Firefox, Mozilla Suite or SeaMonkey. Other Java-related issues include high memory use, browser hangs and security problems.
  • (Windows) You can disable the Adobe Reader browser plugin to force .PDF links to open the Adobe Reader program instead of the Adobe Reader plugin, which, if done via the Adobe Reader program preferences, should remove the "nppdf32.dll" plugin file from all locations (see the Adobe Reader article for additional information).
  • You can disable Quicktime plugins for different filetypes via the Quicktime browser settings from within the MIME settings window, by unchecking the file formats you don't want opened by the associated Quicktime plugin. Note that you may have multiple Quicktime plugins depending on how many file types you have enabled in the Quicktime browser settings.
  • Firefox only: If you just want to disable the plugin for file download actions, but leave the plugin enabled for embedded files, this can be done via your Firefox options for managing file types, as explained in this article.
  • You can install an extension to block content that requires a plugin. For example, the Flashblock extension will block Flash and Shockwave content and NoScript can be configured to block Flash and other plugins [5].

Problematic plugins

Applies to Windows systems

Your Mozilla application, a Mozilla extension or the application that includes the plugin may provide a user interface where you can disable a plugin. See the other methods of disabling plugins given above.

If there is no user interface to disable the plugin, you must manually disable it, either by moving the plugin file to another location or by renaming it (to rename a plugin, add an "X" in front of the file name).

The following plugins have been known to cause problems in Mozilla applications (this is not a complete list). Plugins listed below are located in the browser plugins folder (e.g., for Firefox, in C:\Program Files\Mozilla Firefox\plugins) unless another location is given. Note: Plugin locations can be found by setting plugin.expose_full_path to true in about:config and then checking the file path in about:plugins.

  • np32dsw.dll - The Shockwave plugin can cause an immediate increase in memory usage. Either uninstall the Shockwave Player or disable the plugin.
  • npbittorrent.dll - The Bittorrent plugin can cause an empty Download Actions list of file types.
  • npmozax.dll - The ActiveX plugin will conflict with the the Flash plugin or cause other problems if the wrong version is installed.
  • NPTURNMED.dll - The Turner Media Plugin initiates Data Execution Prevention (DEP) on Windows Vista and crashes Firefox 3 (bug 427382). [6]
  • npvlc.dll - The VLC Media Player plugin can cause a conflict with the Windows Media Player plugin and cause problems viewing Windows Media Video files.
  • npunagi2.dll - This is the AOL Media Playback Plugin. It launches AOLMediaPlaybackControl.exe to play embedded .MP3 files but doesn't work properly [7].
  • npyaxmpb.dll - The Yahoo! activeX Plug-in Bridge plugin may causes crashes when using Yahoo Mail (see the linked article).
  • npYState.dll - The Yahoo! Application State plugin can cause Firefox crashes in Yahoo Mail and on other Yahoo sites. [8] To disable, open the C:\Program Files\Yahoo!\shared folder and rename the file "npYState.dll" to "XnpYState.dll". Note: Yahoo! Application State plugin version 1.0.0.5 and below is blocklisted and automatically disabled in Firefox 3. [9]

Download manager plugins

Download manager plugins are known to cause problems downloading or saving files, if the application is later uninstalled or otherwise stops working, if the associated plugins are still in place. Such plugins include:

  • NPGetRt.dll (GetRight) [10]
  • NPWinGet.dll (WinGet) [11]
  • npdap.dll (Download Accelerator Plus) [12]
  • npfd.dll (FreshDownload) [13]
  • NPNXCatcher.dll, NPNXCatcher(Audio).dll, and NPNXCatcher(Video).dll (Net Transport) [14]

Information about other Download Managers can be found at PluginDoc.

Outdated plugins placed in the browser plugins folder

Outdated versions of plugins that have been copied to the browser plugins folder may conflict with the currently installed version.

See also

External links

Related bug reports