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Will not open as says already running. Systemrestart does not work.

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  • 4 have this problem
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  • Last reply by Abbas

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When attempting to open Firefox the following message appears:

Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system.

Restart does not solve the problem

When attempting to open Firefox the following message appears: Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system. Restart does not solve the problem

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To fix the problem, do the following - 1. First go to task manager and ensure that all instances of Firefox.exe are killed.

the rest of the recommendations were deleted by a moderator - I don't know if this posting was intended as "cute" or not, but advising a Firefox user to delete all their Firefox personal data files is wrong

Modified by the-edmeister