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I have installed Firefox but I keep getting the following message, "Failed to read the configuration file."

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  • 2 have this problem
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  • Last reply by cor-el

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Firefox has stopped working. I have uninstalled it and reinstalled it and it still will not work. It tells me that it installed successfully but when I launch it I get a window that says, "Failed to read the configuration file." and it will not open. Please help.

Firefox has stopped working. I have uninstalled it and reinstalled it and it still will not work. It tells me that it installed successfully but when I launch it I get a window that says, "Failed to read the configuration file." and it will not open. Please help.

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Do a clean reinstall.

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

  • Uninstall your current Firefox version.
  • Do not remove personal data when you uninstall the current version.

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

  • It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.

Your bookmarks and other profile data are stored elsewhere in the Firefox Profile Folder and won't be affected by a reinstall, but make sure that you do not select to remove personal data if you uninstall Firefox.

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I tried what you said and it still gives me the same error message.

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Did you remove the Firefox program folder (C:\Program Files\Mozilla Firefox\)?

Can you attach a screenshot?

Use a compressed image type like PNG or JPG to save the screenshot and make sure that you do not exceed the maximum file size (1 MB).