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Failed to read configuration file contact your system administrator

Posted

I have tried to reinstall firefox to my pc running windows vista several times rebooting my pc unplugging it ect ect still getting the message " Failed to read configuration file contact your system administrator" I have used firefox for years with no major problems. How can I fix this?

Additional System Details

Application

  • User Agent: Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.0; Trident/5.0; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET4.0C)

More Information

cor-el
  • Top 10 Contributor
  • Moderator
10749 solutions 96724 answers

This happens if there is setting to use a mozilla.cfg file in the Firefox installation folder and the file isn't working or missing.

If you didn't install such a file yourself the you should remove the involved files.

Do a clean reinstall and delete the Firefox program folder before reinstalling a fresh copy of Firefox.

Download a fresh Firefox copy and save the file to the desktop.

Uninstall your current Firefox version, if possible, to cleanup the Windows registry and settings in security software.

  • Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you will also lose your personal data like bookmarks and passwords from profiles of other Firefox versions.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

Your bookmarks and other profile data are stored in the Firefox Profile Folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.