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Firefox will not open - it says it has a copy open already - and it does not. This happened after I tried to update to new firefox.

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  • Last reply by cor-el

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I attempted to upload the new version of Firefox. When I did this - I could not open Firefox at all - a box pops up telling me to 'Close Firefox - a copy of firefox is already open - Only one copy of Firefox can be open at a time.

I tried to remove Firefox completely form the computer and reinstall - and I get the same message.

I am using a macbook prop with Lion operating system

I attempted to upload the new version of Firefox. When I did this - I could not open Firefox at all - a box pops up telling me to '''Close Firefox - a copy of firefox is already open - Only one copy of Firefox can be open at a time.'' I tried to remove Firefox completely form the computer and reinstall - and I get the same message. I am using a macbook prop with Lion operating system

All Replies (2)

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Must be the "hang at exit" problem. You already know how to do Step1; now just determine which Add-on (Extension or Plugin) is causing the problem.

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


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