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cannot launch firefox. error message reads " a copy of firefox is already open" though none is open.

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I cannot launch Firefox. Error message reads "Close Firefox. A copy of Firefox is already open. Only one copy of Firefox can be open at a time". But there IS NOT a copy open at all. Even after uninstall and downloading another copy, it will not let me launch. Same error message.

I cannot launch Firefox. Error message reads "Close Firefox. A copy of Firefox is already open. Only one copy of Firefox can be open at a time". But there IS NOT a copy open at all. Even after uninstall and downloading another copy, it will not let me launch. Same error message.

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Please read this article to see if it helps:


http://kb.mozillazine.org/Firefox_hangs#Hang_at_exit