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On our network, when the user is logged on a PC and then tries to login on his laptop he is getting this error: " Windows cannot copy "..\%username%\Application Data\firefox\profiles....\parent.lock file to the local C:..."

I have tried deleting the profiles and also uninstalled firefox, but nothing seems to be resolving the problem.

Any ideas ?

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migrated from Oct 30 '09 at 13:43

This question came from our site for computer enthusiasts and power users.

It sounds like you need to remove the lock file directly from the user's profile directory on the server which stores the user profiles.

The best bet is to delete the file from all possible profile locations (the server, any PCs the user has used, etc.) otherwise the file will magically keep reappearing when they hop between PCs.

You may also want to check the directory/file permissions of the profile as it sits on the server. I have had some pretty strange things happen with permissions/ownership on profile directories in the past.

Lastly, you shouldn't need to blow away the user's entire profile to clean up Firefox. If you want to eradicate Firefox, simply get rid of these directories:

C:\Documents and Settings\USER\Local Settings\Application Data\Mozilla\Firefox

... and ...

C:\Documents and Settings\USER\Application Data\Mozilla\Firefox

That will get you back to a "first time run" state the next time you launch Firefox. No need to anger the user by wiping out his/her entire profile for that!

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Here is an explanation of the parent.lock file (among other things).

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