Use another browser to download the Firefox installer from the Firefox download page and install it.Delete the Firefox installation directory, normally found in one of these locations by default:.(This will not remove your passwords, bookmarks or other user data and settings which are stored in a separate profiles folder.)

The solution is to remove the Firefox program and then reinstall Firefox. This error is caused by a problem with Firefox program files. See How to run Firefox when your profile is missing or inaccessible for solutions. See 'Firefox is already running but is not responding' error - How to fix for solutions. If you get the ' Mozilla Crash Reporter' window when you start Firefox, see Troubleshoot Firefox crashes (closing or quitting unexpectedly) for solutions.įirefox is already running but is not responding Specific error messages Mozilla Crash Reporter

2.4 Firefox will not start because of missing libraries.

2.2 Firefox will not start after installing add-ons.

2.1 Firefox will not start due to security software.

1.6 There was an error launching the application.

1.4 Failed to read the configuration file.

1.3 Your Firefox profile cannot be loaded.

1.2 Firefox is already running but is not responding.

Firefox and windows 10 issues