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Updated yesterday, and now I can't use it at all!

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  • 0 have this problem
  • Last reply by Laura M

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Yesterday, I installed whatever the current version is for Windows 11. At some point after that, it hung. It wouldn't close, even after doing End Task in task manager, nor shutting down the PC.

When I try to start it, it tells me "Firefox is already running, but not responding. The old Firefox process must be closed to open a new window."

Go to task manager, but the only thing I see related to Firefox is under Details pane. Shows a PID but I can't kill it even using the taskkill command as admin:

C:\Windows\System32>taskkill /im "firefox.exe" /t /f SUCCESS: The process with PID 24344 (child process of PID 19568) has been terminated. SUCCESS: The process with PID 15724 (child process of PID 19568) has been terminated. ERROR: The process with PID 32008 (child process of PID 8260) could not be terminated. Reason: There is no running instance of the task. SUCCESS: The process with PID 19568 (child process of PID 20576) has been terminated.

The PID noted above shows a location of C:\Program Files\Mozilla Firefox\tobedeleted, but if I try to delete it (or any other tmp files with yesterday's date), it says they're open in Firefox and won't let me.

Attempted uninstall and reinstall. Same issues as above. Firefox is now unable to be used. I have a ton of bookmarks that I haven't backed up recently by the way. I do NOT want to lose them.

Yesterday, I installed whatever the current version is for Windows 11. At some point after that, it hung. It wouldn't close, even after doing End Task in task manager, nor shutting down the PC. When I try to start it, it tells me "Firefox is already running, but not responding. The old Firefox process must be closed to open a new window." Go to task manager, but the only thing I see related to Firefox is under Details pane. Shows a PID but I can't kill it even using the taskkill command as admin: C:\Windows\System32>taskkill /im "firefox.exe" /t /f SUCCESS: The process with PID 24344 (child process of PID 19568) has been terminated. SUCCESS: The process with PID 15724 (child process of PID 19568) has been terminated. '''''ERROR: The process with PID 32008 (child process of PID 8260) could not be terminated. Reason: There is no running instance of the task.''''' SUCCESS: The process with PID 19568 (child process of PID 20576) has been terminated. The PID noted above shows a location of C:\Program Files\Mozilla Firefox\tobedeleted, but if I try to delete it (or any other tmp files with yesterday's date), it says they're open in Firefox and won't let me. Attempted uninstall and reinstall. Same issues as above. Firefox is now unable to be used. I have a ton of bookmarks that I haven't backed up recently by the way. I do NOT want to lose them.

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Incidentally, if I try to do a refresh via Settings > Apps > Uninstall, it also gives me the "Firefox is already running, but not responding. The old Firefox process must be closed to open a new window." message.

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Topic can be deleted. I somehow managed to beat it into submission enough to be able to uninstall/reinstall. Didn't lose anything, either. :)

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