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Cannot open Firefox

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  • 0 have this problem
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  • Last reply by Terry

bsimonov
bsimonov
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I cannot open Firefox. Error message appears: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window."

Task Manager always shows three active Firefox Apps, but ending those tasks does not help. I don't see any other active Mozilla procces on the list

I have uninstalled and reinstalled Firefox from MS Store but that does not help either.

I cannot open Firefox. Error message appears: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." Task Manager always shows three active Firefox Apps, but ending those tasks does not help. I don't see any other active Mozilla procces on the list I have uninstalled and reinstalled Firefox from MS Store but that does not help either.

All Replies (1)

Terry
Terry
more options

You may have to remove a lock file.

https://support.mozilla.org/en-US/kb/Firefox-already-running-not-responding https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data#w_finding-your-profile-without-opening-firefox