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Doesn't start when starting as administrator. Error 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.

  • 5 replies
  • 12 have this problem
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  • Last reply by Hasan

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Update firefox, it asked me to update flash, I tried to update flash but it said I had to close firefox. A box came up and said the Flash install would continue when I closed firefox. I closed all firefox windows and no update of flash occurred. I tried relaunching firefox but got the "Doesn't start when starting as administrator. Error 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." message. I rebooted the system, no improvement. I tried to run firefox as administrator and got the same message. Either I find a fix or I won't be able to use firefox and will have to go back to ie.

Update firefox, it asked me to update flash, I tried to update flash but it said I had to close firefox. A box came up and said the Flash install would continue when I closed firefox. I closed all firefox windows and no update of flash occurred. I tried relaunching firefox but got the "Doesn't start when starting as administrator. Error 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." message. I rebooted the system, no improvement. I tried to run firefox as administrator and got the same message. Either I find a fix or I won't be able to use firefox and will have to go back to ie.

All Replies (5)

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-> press CTRL + SHIFT + ESC to Open Task Manager -> Processes tab -> right-click firefox.exe and click End Process Tree -> close Task Manager

Troubleshooting extensions and themes

Troubleshooting plugins

Check and tell if its working.

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I had already gone to the Task Manager and firefox.exe didn't show as an open process but now I know what to look for process-wise if I have similar problems. I was able to go to Mozilla.com and download Version 6, install it. The install program prompted an update of Flash, which I then installed. Thereafter Firebox worked again.

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I have reinstalled and up/down graded the versions and even installed in different locations/harddrives. This all started after a fresh windows install after a crash.

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