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when trying to open firefox, I receive a message that firefox is already running, to open must close application or restart computer.

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When I attempt to start firefox by clicking on the icon, I receive a message that firefox is already running (it's not) and that I must close the program or restart the computer. Since I cannot close the program since it is not running, Imust restart the computer which is time consuming.

When I attempt to start firefox by clicking on the icon, I receive a message that firefox is already running (it's not) and that I must close the program or restart the computer. Since I cannot close the program since it is not running, Imust restart the computer which is time consuming.

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I just went through this a couple of days ago. Hasn't happened in yrs, before the other day. If its not listed in the taskmgr., then its really not running. Its the "parent.lock" file in your profile that needs to be deleted. If you can get into your profile folder, if the file is in there, delete it. If not, you may have to uninstall ff, then reinstall ff. Hope you have your profile(s) or at least your bookmarks backed up. Luckily I had bookmarks from both profiles backed up to a cd & a flash drive, two backups in case one doesn't work, because I recently had to reformat my pc. When you get it cleared up, it pays to back up your profile(s) in case something like this happens. In case you don't know how, go to>organize bookmarks>click all bookmarks>import-backup to whatever you use. Or you can use one of the addon profile backup programs.

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Since updating to Firefox 12.0 the other day, I'm getting the error message: Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system.

It's not in my task bar and I can't continue to restart my computer every time I want to exit and restart a browser.

I attempted to understand the instructions given here, they aren't terribly clear to a non-geek. However I did check my Control Panel and Admin Tools to find there was something regarding PROFILE there. There was nothing about anything being locked. Sorry but also did not understand the instructions for backing up BookMarks. I see nothing regarding backing these up in the Bookmark pull down menu. It would be best to give more complete answers when possible as many never had to do these things before and may not be technically savvy.

Anyway, I guess I will have to stop using Firefox or revert to the old version, if it's possible. I suspect this is some new bug in the new version and I can't be the only one effected.

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Create a new profile as a test to check if your current profile is causing the problems.

See "Basic Troubleshooting: Make a new profile":

There may be extensions and plugins installed by default in a new profile, so check that in "Tools > Add-ons > Extensions & Plugins" in case there are still problems.

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

See: