Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

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If you are having problems with pages that use plugins (such as Flash, Java, and more) to display content, you may need to check to see whether a plugin is causing the problem.

Common problems caused by plugins include:

This article describes how to troubleshoot plugins. If you are having a problem with an extension or theme, see Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems. For general information on plugins, see Use plugins to play audio, video, games and more.

Determining if a plugin is the problem

You can selectively disable plugins while Firefox is running. If you suspect a certain plugin, disable it first, then test for your problem. If you don't know which plugin to disable:

  1. Click the menu button Fx57menu , click Fx57Addons-icon Add-ons and select Plugins.
  2. Select a plugin in the list and then click its Disable button. Repeat this step for each plugin in the list. You do not need to restart Firefox for the changes to take effect.
  3. Test for your problem. If it does not occur, go back to the Add-ons Manager tab and re-enable plugins one-by-one with the Enable button until you find which one causes your problem to occur.
  1. Click the menu button Fx57menu , click Fx57Addons-icon Add-ons and select Plugins.
  2. Select a plugin in the list and then select Never Activate in its drop-down menu. Repeat this step for each plugin in the list. You do not need to restart Firefox for the changes to take effect.
  3. Test for your problem. If it does not occur, go back to the Add-ons Manager tab and re-enable plugins one-by-one with the Always Activate drop-down menu until you find which one causes your problem to occur.

If you find that disabling a plugin fixes your problem, continue following the steps in this article.

Updating or re-installing your plugins

Many problems with plugins can be solved by updating to the latest version of the plugin.

If updating to the newest version of the plugin or reinstalling it does not fix the problem, you can leave it disabled.

Manually uninstalling a plugin

If you can't use an uninstaller program to remove a plugin, you can remove it manually:

  1. Type about:config in the address bar and press EnterReturn.
    A warning page may appear. Click I accept the risk!Accept the Risk and Continue to continue to the about:config page.
  2. Search for the preference: plugin.expose_full_path.
  3. Double-click on the plugin.expose_full_path preference in the list to change the value to true.
  4. Enter about:plugins into the Location bar and press EnterReturn to display the About Plugins page.
  5. Each entry in the About Plugins page will have "File name:" followed by a path. Use Windows Explorer to navigateNavigate to the folder shown for the plugin you want to remove.
  6. Rename the file to add an X in front of the filename (for instance, npswf32 becomes Xnpswf32).
  7. Double-click on the plugin.expose_full_path preference in the list on the about:config page to change the value back to false to avoid exposing the plugin path to websites.

The plugin will be removed.

If you can't use an uninstaller program to remove a plugin, you can remove it manually:

  1. Type about:plugins into the Location bar and press EnterReturn to display the About Plugins page.
  2. Each entry in the About Plugins page will have "File name:" followed by the name of the plugin. You can inspect the contents of the "pluginreg.dat" file (with a text editor) in your Firefox profile folder to find the location for each plugin. Use Windows Explorer to navigateNavigate to the folder shown for the plugin you want to remove.
  3. Rename the file to add an X in front of the filename (for instance, npswf32 becomes Xnpswf32).

The plugin will be removed.

If you can't use an uninstaller program to remove a plugin, you can remove it manually:

  1. Type about:plugins into the Location bar and press EnterReturn to display the About Plugins page.
  2. Each entry in the About Plugins page will have "File:" and "Path:", showing the name and location of the plugin file. Use Windows Explorer to navigateNavigate to the folder shown for the plugin you want to remove.
  3. Rename the file to add an X in front of the filename (for instance, npswf32 becomes Xnpswf32).

The plugin will be removed.

Re-initializing the plugins database

In some cases, you may not be able to install or re-install a plugin. Re-initializing the plugins database may fix this problem:

  1. Open your profile folder:

    • Click the menu button Fx57menu , click Help and select Troubleshooting Information.From the Help menu, select Troubleshooting Information. The Troubleshooting Information tab will open.
    • Under the Application Basics section next to Profile FolderDirectory, click Open FolderShow in FinderOpen Directory. A window will open that contains your profile folder.Your profile folder will open.
    Note: If you are unable to open or use Firefox, follow the instructions in Finding your profile without opening Firefox.

  2. Click the Firefox menu Fx57Menu and select Exit.Click the Firefox menu at the top of the screen and select Quit Firefox.Click the Firefox menu Fx57Menu and select Quit.
  3. Delete the pluginreg.dat file.
  4. Open Firefox
  5. In the Location bar type about:plugins and press EnterReturn to bring up the Firefox plugins list.