Firefox crashes

This article deals with Firefox closing unexpectedly, or closing after an error dialog appears. If Firefox hangs, freezes, or stops responding to user input, see Firefox hangs.

If Firefox is crashing, first make sure you are using the latest public release version of Firefox, which will have the most recent fixes. You can download and install the latest version of Firefox from mozilla.com or choose Help -> Check for Updates. You may also wish to review the Firefox release notes for your Firefox version, to see if the issue and solution is listed under "Known Issues".

Crash logs may help you to locate the problem. See Still experiencing problems?, below.

Extensions

Problematic extensions may cause crashes. Start in Firefox Safe Mode, which disables all extensions, to help determine if an extension is causing the problem.

Plugins

Plugins are programs that work within Firefox and allow you to experience multimedia content such as video, animation or sound. Plugins can crash within their own code, and can also cause a crash within Firefox code. Plugins that can crash Firefox include:

• Adobe (Macromedia) Flash
• Shockwave
• Real Player or Real Alternative
• Java
• VLC Media Player
• Yahoo! Application State plugin for Yahoo! Mail

Note: In this example, the Flash plugin was found to crash both Firefox and a non-Mozilla browser. The source of the crash was confirmed by the Windows Event Viewer ( see below).

Try updating your plugins to the latest versions. For basic plugin information, install instructions and download links, visit PluginDoc. You can also temporarily disable your installed plugins to see if the crashes stop, by renaming or removing the associated plugin file or, in Firefox 3, by disabling the plugin via "Tools -> Add-ons -> Plugins" (see Issues related to plugins for details).

VLC Media Player

If you are using the VLC Media Player plugin, Firefox may crash when viewing WMV media. The VLC Media Player browser plugin conflicts with the Windows Media Player plugin, so you need to disable the plugin or remove the VLC plugin file "npvlc.dll" from the Firefox installation directory plugins folder, for embedded WMV files to play properly.

Yahoo! Application State

If you have installed Yahoo! Messenger on your system, you may experience crashes when using Yahoo! Mail. This is caused by the Yahoo! Application State plugin (bug 322363, bug 326344). Note: The Yahoo! Application State plugin (v.1.0.0.5 and older) is on the Mozilla Add-ons Blocklist and should be automatically disabled in Firefox 3. [1]

To see if this plugin is the cause of your problems, type about:plugins in the Location Bar and press Enter. If you find "Yahoo! Application State" ("npYState.dll") in the installed plugins list, exit Firefox, open the C:\Program Files\Yahoo!\shared folder and rename the file "npYState.dll" to "XnpYState.dll" to disable the plugin. In Firefox 3, you can also disable the plugin, if found, via "Tools -> Add-ons -> Plugins". Open Firefox and test Yahoo! Mail.

Other installed software

Other installed software that is running on your computer may be causing Firefox to crash.

• Spector Pro for Windows computer monitoring software can cause Firefox 3 to crash at startup or when opening a new tab. If you use this product, try updating to the latest version or contact SpectorSoft Support. [2] [3] [4]

Crash when downloading

Try clearing the download history from the Clear Private Data tool, located on the Tools menu. In Firefox 2 and below, you may need to exit Firefox completely and delete the downloads.rdf file in the Firefox profile folder (read this if you need help finding it). For more information, see Unable to save or download files.

Crash when starting Firefox

• Older versions of the Google Desktop application can cause Firefox 3 to crash at startup. [5] Uninstall Google Desktop and then download and install the latest version.

Crash when closing Firefox

The Google Web Accelerator application causes Firefox to crash on closing. [6] You can uninstall Google Web Accelerator from the Windows Control Panel list of installed programs ("Add or Remove Programs" list). [7]

Damaged plist file - Mac OS X

On Mac OS X, sometimes a recurring crash pattern is caused by a preference file being damaged. Quit Firefox, then go to your user Library -> Preferences, find the file "org.mozilla.firefox.plist" and move it to your desktop (don't trash it; just leave it on the desktop). When you restart Firefox, a new .plist file will be generated. If the new preferences file is working well, you can trash the .plist file on the desktop. More information on corrupt .plist files can be found here. [8]

Windows compatibility mode

On Windows XP, sometimes Firefox must be run in Windows 2000 compatibility mode. Right click on your Firefox desktop icon and click on Compatibility > change the setting to Windows 2000 > click Apply.[9]

Hardware problems

Hardware problems, especially bad RAM chips, can cause Firefox to crash. [10] Download Memtest86 for Windows and Intel Linux or Rember for Mac to test if you have bad RAM chips.

Still experiencing problems?

• The standard diagnostic may resolve crashes not specifically mentioned in this article.
• Older versions of video card drivers can cause crashes. Make sure your drivers are up to date.
• Make sure Talkback (Firefox 2) or Breakpad (Firefox 3) is installed and enabled. Post on the Firefox Support forum what steps cause Firefox to crash and your Talkback crash ID or Breakpad report ID. Those who read it may be able to look up your crash on the Talkback website and find an existing bug report or file a new one for you. Also, if the crash you experience is common, it may be marked as a "topcrasher", making it more likely to be fixed in the next release.
• Your operating system system log may also have a crash report. The information will probably include the name of the module that caused the crash. On recent Windows versions, go to Start > Settings > Control Panel > Administrative Tools > Event Viewer. In the application tab, right-click on the event and select Properties. When you report the event, you should copy the information from the log.
• It might be a good idea to do a malware sweep.

External links

• Firefox crashes (Firefox Support)