Firefox not starting: tip!

OK say you launch Firefox and nothing happens. You try again, and again, and still get no result. First thing to try is launching the task manager, either in XP or Vista. If you see firefox.exe is running, just end the process, and try again. If it still does not work, go to your profile folder and see if a file named "parent.lock" still appears. This file is supposed to be naturally erased everytime Firefox is closed normally. It's there when Firefox is in use to tell the system that your profile is in use. Well now, after a crash from Firefox, this file might still reside in your profile, and block a Firefox restart. Then just delete parent.lock, and restart Firefox. That should work.
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