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I am getting the following reading when I click on Firefox: "The application or DLLc:/programfiles/mozillafirefox/xul.dll is not a valid windows image


I am getting the following pop up reading when I click on the Mozilla Firefox icon located on my desktop: "The application or DLL c:/program files/mozillafirefox/xul.dll is not a valid windows image" I have always used mozilla and now I have no connection to the internet with it. I have tried to go to Mozilla.com to download again and I can't seem to locate a version to download.

Additional System Details


  • User Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30)

More Information

rjohnson19 39 solutions 240 answers

michaeleen, you can fix this with a clean install of Firefox:

1. Download the Firefox installer from this direct link and save it to your desktop or other location.

  2. Make sure that Firefox is closed completely
  3. Delete the Firefox installation directory (On Windows, this is typically the C:\Program Files\Mozilla Firefox folder that contains "firefox.exe" and other Firefox program files and folders).
  4. Reinstall Firefox by running the installer you downloaded previously.

Your personal settings, including bookmarks and history, will not be lost.

See http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Clean_reinstall