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I cannot open Firefox.

  • 3 replies
  • 2 have this problem
  • 2 views
  • Last reply by Shadow110

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I tried uninstalling and re-installing. Still cannot open. When I try to install again, it says that Firefox is already open.

I tried uninstalling and re-installing. Still cannot open. When I try to install again, it says that Firefox is already open.

All Replies (3)

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Hi, please try this : Open Task Manager and End all Firefox processes then : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 59.0.2 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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The above steps didn't work. Firefox still refuses to open.

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Hi, please grab a copy of your profile :

Then if Uninstall did not work please try https://www.revouninstaller.com/revo_uninstaller_free_download.html then install from the installer downloaded from above.

You can try reinserting your Profile and see if all things work or if does not follow below instructions.

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over the problem. Never work with original files.

Please let us know if this solved your issue or if need further assistance.