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Can't Open Browser

  • 3 majibu
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  • Last reply by cor-el

cliffordblau
cliffordblau
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This problem started yesterday. Right after turning on the computer (Windows 10), if I try to start Firefox (or other browsers based on it), I get a message saying "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." Of course, since I just started the computer, no old process is running. I've looked in Resource Monitor and Task Manager to be sure. If I click on "Close Firefox" I just get the same message again. I installed the latest version of Firefox. I deleted one of the other browsers and reinstalled it. I've tried doing a clean boot. Nothing helps. Meanwhile, I can still open browsers not based on Mozilla.

This problem started yesterday. Right after turning on the computer (Windows 10), if I try to start Firefox (or other browsers based on it), I get a message saying "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." Of course, since I just started the computer, no old process is running. I've looked in Resource Monitor and Task Manager to be sure. If I click on "Close Firefox" I just get the same message again. I installed the latest version of Firefox. I deleted one of the other browsers and reinstalled it. I've tried doing a clean boot. Nothing helps. Meanwhile, I can still open browsers not based on Mozilla.

All Replies (3)

cor-el
cor-el
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  • Top 10 Contributor
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You can check this article:

cliffordblau
cliffordblau Mwenye swali
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Deleting the parent.lock file worked on two out of three browsers. Oddly not on the one I reinstalled. I'll try deleting and reinstalling it again.

cor-el
cor-el
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  • Top 10 Contributor
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You can create a new profile as a quick test to see if your current profile is causing the problem.

See "Creating a profile":

If the new profile works, 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 problems.