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When I try to start Firefox I get 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.

  • 2 respostas
  • 13 have this problem
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  • Last reply by Hasan

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I get this message when I try to start Firefox after first logging on after turning on the computer.

   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.
Have rebooted. Works when Administrator logs in, just does this in my user profile. Have also re-intalled. Mo change in my User account.
 Firefox was working fine for the last 3 1/2 years.  Any suggestions?
I get this message when I try to start Firefox after first logging on after turning on the computer. 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. Have rebooted. Works when Administrator logs in, just does this in my user profile. Have also re-intalled. Mo change in my User account. Firefox was working fine for the last 3 1/2 years. Any suggestions?

All Replies (2)

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Firefox is "hanging at exit" when you exit/quit Firefox.

  1. Stop the Firefox process:
  2. Why Firefox may hang:
  3. Use Firefox Safe Mode to find a problem with an Extension or Plugin:


If this reply solves your problem, please click "Solved It" next to this reply when signed-in to the forum.

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Firefox is already running but is not responding

Profile in use

Check and tell if its working.