How to Run Firefox in Safe Mode

by Contributor

Running Firefox in Safe Mode can troubleshoot problems with a Firefox browser. Start Firefox in Safe Mode and turn off extensions, themes and personal customizations to identify the problem, and modify your Firefox browser as necessary.

Exit all Firefox and Thunderbird applications. Check the Task Manager to make sure all active operations close. If you find open programs, highlight them and click End Task.

Click on the Start menu, and then select Run.

Enter "firefox -safe-mode" in the dialog box's text field. Select Continue in Safe Mode.

Know your browser will temporarily revert to its defaults while you are in Safe Mode. Check the browser for problems while in Safe Mode. Make modifications or remove troublesome add-ons.


  • check Look for a safe mode shortcut under your Start menu to save time. It should be located under your Firefox program folder.
  • check In the Safe Mode dialog box, you have the option to make specific changes permanent before clicking Continue in Safe Mode. If you'd like to permanently disable add-ons or reset toolbars, controls, bookmarks, user preferences and search engines, check the option and choose Make Changes and Restart when the option highlights and becomes available. Otherwise, all of Safe Mode's features will be temporary.