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I upgraded to Firefox 6 and now when I try to open it, a window says there's already a copy of Firefox open and there can only be one at a time but there is no other copy!

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  • Last reply by Chouette

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I was trying to update my Firefox profile from my old computer and it didn't work and as I was in the middle of that process I was prompted to upgrade to Firefox 6 which I did. But now when I try to open Firefox, it won't let me because it says there's another copy already open. I have taken everything related to Firefox except the brand new version of it I just downloaded off my computer and I still get that message. What should I do?

I was trying to update my Firefox profile from my old computer and it didn't work and as I was in the middle of that process I was prompted to upgrade to Firefox 6 which I did. But now when I try to open Firefox, it won't let me because it says there's another copy already open. I have taken everything related to Firefox except the brand new version of it I just downloaded off my computer and I still get that message. What should I do?

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Try to create a new profile as a test to check if your current profile (if you still have it) is causing the problems.

See Basic Troubleshooting: Make a new profile:

If that new profile works then you can transfer some files from the old profile to that new profile (be careful not to copy corrupted files)

See:

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I have a similar problem; but I think the cause of the "already running" message is that my computer crashed. I rebooted before I learned to look for the parent lock file, but even when I knew to look for it, I found my original profile folder to be empty. So I created another profile folder, and FF works, but I cannot access my old profile folder. When I open the location where it should be, nothing's there. But if I go to profile manager, I see my original profile is still there (and it has a location, it's where it should be - and where it's invisible, but even if I type in this location, nothing comes up). I tried making all folders visible (I run Windows 7), but this did not make my old profile visible. I want to find it because of the bookmarks I bookmarked recently.