Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

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!

  • 2 odgovori
  • 4 ima ovaj problem
  • 3 views
  • Posljednji odgovor poslao Chouette

more options

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?

All Replies (2)

more options

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:

more options

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.