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After I close Firefox 4.0 and try to open it later, it says that another instance of firefox is already open and won't let me open firefox. I have to restart computer..

glozy
glozy
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After it closes I work on another program, etc. When I try to go online again firefox says it's still open even though I can see nothing. Going to Task Manager doesn't show anything open. I'm running Windows 7 64-bit.

After it closes I work on another program, etc. When I try to go online again firefox says it's still open even though I can see nothing. Going to Task Manager doesn't show anything open. I'm running Windows 7 64-bit.

All Replies (1)

the-edmeister
the-edmeister
  • Moderator
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https://support.mozilla.com/en-US/kb/Firefox%20hangs
See hang-at-exit