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Firefox crashes

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  • 1 has this problem
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  • Last reply by cor-el

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Beginning just today, when I try to open Firefox, I get the message: Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window. with the option to Close Firefox or cancel. When I click close firefox, I get a message: Your Firefox profile cannot be loaded. It may be missing or inaccessible. I have tried uninstalling and reinstalling, restarting my machine. I'm at a loss. I have no idea why this is happening and can't seem to fix it! Help!!!

Beginning just today, when I try to open Firefox, I get the message: Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window. with the option to Close Firefox or cancel. When I click close firefox, I get a message: Your Firefox profile cannot be loaded. It may be missing or inaccessible. I have tried uninstalling and reinstalling, restarting my machine. I'm at a loss. I have no idea why this is happening and can't seem to fix it! Help!!!

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This issue can be caused by a problem with the profiles.ini file or with the permissions (owner) of involved folders.

You can use one of these to make Firefox create a new default profile or recover an existing profile:

  • Delete the profiles.ini file to make Firefox create a new (default) profile
  • Use the Profile Manager to create a new profile
    If you still have an existing profile then click "Choose Folder" in the Profile Manager and browse to the location of a lost profile to recover this profile
    https://support.mozilla.org/kb/Managing+profiles

You should find the profiles.ini file in this hidden location:

  • Windows: %AppData%\Mozilla\Firefox\
    *C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\
  • Mac: *~/Library/Application Support/Firefox/
  • Linux: *~/.mozilla/firefox/

If clearing the profiles.ini file isn't working then also check the location of the cache files.

  • Windows: *C:\Users\<user>\AppData\Local\Mozilla\Firefox\Profiles\<profile>\
  • Mac: *~/Library/Caches/Firefox/Profiles/
  • Linux:*~/.cache/mozilla/firefox/

You can also try to rename/delete the Mozilla\Firefox\ folder in both above mentioned locations (main, cache).

"AppData" (XP: Application Data; Mac: ~/Library; Linux: ~/.mozilla) is a hidden folder.