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Firefox is already running but not responding,No process in task manager,Restart and uninstall not useful.Profile manager error

  • 5 replies
  • 22 have this problem
  • 6543 views
  • Last reply by cor-el

Quinn777
Quinn777
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So one day when I opened my mozilla firefox Ive got the "Firefox is already running but not responding.To open a new window,you must first close the existing firefox process,or restart your system." So I checked my task manager but there is no process,I then checked hours in the internet to find a solution.Yes,I also checked for solutions in this site.Then,I try uninstalling and restarting,it also didn't work,Next I also tried downloading profilemanager and tried to run it but as unlucky as I can be,it also didn't work. Please help :(

So one day when I opened my mozilla firefox Ive got the "Firefox is already running but not responding.To open a new window,you must first close the existing firefox process,or restart your system." So I checked my task manager but there is no process,I then checked hours in the internet to find a solution.Yes,I also checked for solutions in this site.Then,I try uninstalling and restarting,it also didn't work,Next I also tried downloading profilemanager and tried to run it but as unlucky as I can be,it also didn't work. Please help :(

All Replies (5)

iamjayakumars
iamjayakumars
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The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

  1. Go to Firefox > Help > Troubleshooting Information.
  2. Click the "Reset Firefox" button.
  3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
  4. Firefox will open with all factory defaults applied.


Further information can be found in the Refresh Firefox - reset add-ons and settings article.

Did this fix your problems? Please report back to us!

Modified by iamjayakumars

Quinn777
Quinn777 Question owner
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My firefox keeps giving me the "Firefox is already running but not responding" notice so I can't open the browser,thus unabling myself to use your recommended solution. If you can,could you please give me another solutions? Thx :(

iamjayakumars
iamjayakumars
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Goto File > Quit

Quinn777
Quinn777 Question owner
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where can I find this file->quit?

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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This can happen when the profile that is marked in the profiles.ini file as Default=1 is missing or otherwise can't be used.

If there is still a profiles.ini file, but the profile folder is gone then delete the profiles.ini file to force Firefox to create a new default profile.
Otherwise you can create a new profile and use "Choose Folder" to recover an existing profile.