Some problems with Firefox are caused by extensions or themes. This article will help you determine whether an extension or theme is causing your problem and, if it is, describe how to make Firefox run normally again.

Índice de contenidos

• Start Firefox in Safe Mode
• The problem still occurs in Safe Mode
• The problem does not occur in Safe Mode
• Switch to the default theme
• Disable all extensions
• Test for faulty extensions
• Updating themes
• Updating extensions

Start Firefox in Safe Mode

When you start in Firefox's Safe Mode, all extensions are temporarily disabled and the default theme is used. This will help determine whether an extension or theme is causing your problem.

1. Close down Firefox completely: At the top of the Firefox window, click the File menu, and select the Exit menu item.Close down Firefox completely: On the menu bar, click the Firefox menu, and select the Quit Firefox menu item.Close down Firefox completely: At the top of the Firefox window, click the File menu, and select the Quit menu item.
2. In Windows, click Start, open the All Programs list, and navigate to the Mozilla Firefox folder. In the Mozilla Firefox folder, select Mozilla Firefox (Safe Mode).Hold down the option key, as you start Firefox.Go to your Terminal and run:

   firefox -safe-mode

   You may need to specify the Firefox installation path (e.g. /usr/lib/firefox-3.5). Firefox should start up with a Firefox Safe Mode dialog.
   
   Note: You can also start Firefox in Safe Mode by clicking Start, selecting Run (or use the Start Search box in Windows 7 and Vista) and then entering the following in the text field:
   

   firefox -safe-mode

3. When the Firefox Safe Mode window appears, press the button Continue in Safe Mode.

After Firefox starts in Safe Mode, test for your problem.

The problem still occurs in Safe Mode

If your problem persists in Safe Mode, it is not being caused by an extension or theme. Other possible causes could be plugins or changes made to Firefox preference settings, which are not disabled in Safe Mode.

• For additional troubleshooting suggestions, see Solución básica de problemas, Troubleshooting plugins, and Resetting preferences.

The problem does not occur in Safe Mode

If your problem did not occur in Safe Mode, it is most likely because of an extension or theme. Continue following the steps in this article to determine whether an extension or theme is causing your problem.

Switch to the default theme

If you are using a theme other than the default Firefox theme:

1. Click on the Tools menu, and select Add-ons. The Add-ons window appears.
2. In the Add-ons window, click the Themes panel.
3. Select the default theme, then click the Use Theme button, to make Firefox switch to that theme.
4. Click Restart Firefox.

After you restart Firefox, test for your problem. If it no longer occurs, the theme you were using was causing it. If it still occurs, continue following the steps in this article.

Disable all extensions

To determine whether a faulty extension is causing your problem, you can disable all of your installed extensions:

1. Click the Tools menu and then select Add-ons. The Add-ons window appears.
2. In the Add-ons window, click the Extensions panel. The list of installed extensions appears.
3. Click the name of an extension the list to select it.
4. Click Disable to disable the selected extension.
5. Repeat for each of the other extensions in the list.
6. Click Restart Firefox.

After you restart Firefox, all extensions will be disabled. Test for your problem.

• If the problem still occurs with all extensions disabled, it is most likely that the localstore.rdf file in your Firefox profile is corrupt. You can Reset toolbars and controls to resolve the problem.

If the problem no longer occurs with all extensions disabled, one of your extensions was causing it. To find the extension that was causing your problem, continue as follows:

Test for faulty extensions

To determine which of your disabled extensions was causing your problem, you can re-enable each extension one at a time.

1. Click the Tools menu and then select Add-ons. The Add-ons window appears.
2. In the Add-ons window, click the Extensions panel. The list of installed extensions appears.
3. Click the name of an extension the list to select it.
4. Click Enable to enable the selected extension.
5. Click Restart Firefox.

After you restart Firefox, test for your problem. If the problem comes back, the extension you just enabled was causing it.

After you find the extension that was causing your problem, disable or uninstall the faulty extension and re-enable the other extensions in the Add-ons window.

Updating themes

If an installed theme was causing your problem, it may have an update available that will fix it:

1. Click on the Tools menu and then choose Add-ons. The Add-ons window appears.
2. In the Add-ons window, click the Themes panel.
3. To check for updates for installed themes, click Find Updates.
4. If updates are found, install them by clicking Install Updates.
5. When the installation is complete, click Restart Firefox.

After Firefox restarts, your themes will be updated. If the theme that was causing your problem had an update, re-enable it and test for your problem again.

Updating extensions

If an extension was causing your problem, it may have an update available that will fix it:

1. Click the Tools menu and then choose Add-ons. The Add-ons window appears.
2. In the Add-ons window, click the Extensions panel.
3. Click Find Updates.
4. If updates are found, install them by clicking Install Updates.
5. When the installation is complete, click Restart Firefox.

After Firefox restarts, your extensions will be updated. If the extension that was causing your problem had an update, re-enable it and test for your problem again.