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why do I get this error message after I log off then try to log back on: 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.

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Why do I get this error message when I try to re-log on to Firefox when I have already log off? 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. The only way I can re-log on to Firefox is to restart my computer.

Why do I get this error message when I try to re-log on to Firefox when I have already log off? 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. The only way I can re-log on to Firefox is to restart my computer.

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It sounds as though Firefox is not shutting down completely. Check the "Hang at exit" section of this article for troubleshooting suggestions: http://kb.mozillazine.org/Firefox_hangs#Hang_at_exit