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Firefox is already running, started with the latest upgrade

  • 2 replies
  • 15 have this problem
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  • Last reply by Tom716

Tom716
Tom716
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I have been running Firefox with Win7 for several months with no problems. Suddenly on two separate computers I'm frequently getting the error that Firefox is already running. I open the task manager, end the process, and it works fine. But it will happen again, not every time, but frequently enough that I'm certainly noticing. On one occasion I was unable to find a firefox process listed. But after trying to launch again and getting the error, I was able to find the process and stop it. That only happened once.

I have been running Firefox with Win7 for several months with no problems. Suddenly on two separate computers I'm frequently getting the error that Firefox is already running. I open the task manager, end the process, and it works fine. But it will happen again, not every time, but frequently enough that I'm certainly noticing. On one occasion I was unable to find a firefox process listed. But after trying to launch again and getting the error, I was able to find the process and stop it. That only happened once.

All Replies (2)

Michael Verdi
Michael Verdi
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There are some additional solutions in our article on this topic - "Firefox is already running but is not responding" error - How to fix.

You might also want to see - Firefox hangs when you quit it as this seems to be an ongoing issue for you.

Tom716
Tom716 Question owner
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Thanks. I did look at the first thread. I know how to fix it each time, i.e., kill the process, but don't know how to prevent it from happening. As I said, something has changed. I realized after the post, that I've also recently upgraded my Norton's Internet Security to the 2013 version. That might also be related.

I don't experience Firefox hanging on close though I suppose if the process doesn't end then it is hanging on a system level. In other words, it appears to close normally every time. I'll take a look at that thread.

Thanks again for posting.