"A copy of Firefox is already open. Only one copy of Firefox can be open at a time."

Posted by Isaac Waller on Super User See other posts from Super User or by Isaac Waller
Published on 2009-07-20T05:49:21Z Indexed on 2010/05/21 0:32 UTC
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firefox

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quit

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close

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mac

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osx

I cannot start Firefox on my Mac. It just says "A copy of Firefox is already open. Only one copy of Firefox can be open at a time." I have tried restarting the computer. Any fixes?

You have suggested deleting the lock files in my profile, but, I don't have a profile. I was trying to fix the problem in question http://superuser.com/questions/3275/firefox-on-mac-slow-slow-slow by deleting my profile, so I deleted it, and this came up. So I cannot delete the lock files because they don't exist.

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