The Profile In Use Bug
Excerpts from the Mozilla Firefox Knowledge Base
Browser will not start up:
If Firefox used to work correctly, but it no longer starts when you
try to run it, then this article may help. Before deleting anything,
please back up your profile.
If you receive the "profile is in use" error when trying to launch the
application, this means the profile is locked.
When Firefox is in use, it locks the active profile to keep other
programs from altering the contents or causing conflicts. This lock is
normally transparent to the user, but sometimes the profile remains
locked when it's not expected. Thus, if you launch the application and
the Profile Manager says that your profile is already "in use", it's
telling you that the profile is locked.
At this point check the Task Manager (CTRL+ALT+DEL) and
look for firefox.exe, highlight, and End Task, or End Process. Note
that firefox.exe may be listed more than once.
If Firefox still doesn't start, check the profile for the "parent.lock"
file. If the file is listed, delete the file in order to end the
locked profile process. Further explanation below.
If neither of the workarounds solve the locked process, create a new
Profile for Firefox.
This problem can occur for several different reasons:
- The application may not have shut down completely the last time it
was used. Check for any open windows. Go through your list of running
processes to see if the application is still running in the background.
If it is, ending that process should unlock the profile.
- The application may have shut down abnormally, leaving the lock in
place. To fix this, find your profile and delete the file named
"parent.lock" (Windows), "lock" (Linux), or ".parentlock" (Mac OS X).
In OS X you need to use a free utility like Onyx or Maintain to turn
on visibility for invisible files to show ".parentlock". This file
contains no information, and deleting it will unlock the profile.
- Netscape 7 or another Mozilla-based program may be using the
profile. Try shutting down this program to unlock the profile.
Additionally, you should create separate profiles for each different
application. Especially if you use both Mozilla Suite and Netscape 7,
corruption can result from sharing the same profile between two
different programs. (This problem is unlikely with Firefox and
Thunderbird, since they do not share profiles with other applications
in the way that Mozilla Suite and Netscape 7 can share profiles.)
- If you are running the application from removable media on a
Windows system, open the "profiles.ini" file (located up a few levels
in the folder hierarchy from your profile folder) and make sure that
the drive letter and path to your profile are correct.
- This problem can also occur if you don't have the rights to edit the files in the profile (or create the lock file in the first place). Please note that this can happen if you try to use a profile from a file system mounted with read-only (e.g. a remote Windows share which doesn't have "allow network users to change my files" checked). This can be pretty tricky to diagnose because there is no lock file in the profile, yet the same message appears (profile in use).
If you have startup problems, then post your questions on the:
WindowsBBS Netscape and Mozilla Forum.
I'm a Moderator on the Forum, and along with the other informed
Netscape and Mozilla users and members,
will be happy to provide you with any further assistance you might require.
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