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I continue to have a problem with this 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.I have tried everything .

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  • Last reply by glynes

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I continue to have a problem with this 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.I have tried everything that the internet has suggested but it continues to create havoc....Please help...John.I can't give any more details other than this has become very annoying

I continue to have a problem with this 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.I have tried everything that the internet has suggested but it continues to create havoc....Please help...John.I can't give any more details other than this has become very annoying

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I have the same problem (on Win XP)... if I use Firefox 4 just once, then close the program... I can not restart with out rebooting my system. This is a problem because as a gamer I can not usually restart my computer to look up information as I am in the middle of playing.

So far all I have found is to open the task manager ctrl + alt+ del and find the "running" but unseen version of Firefox on the Processes tab... and close it.

This is not a very good solution... but works. I am then able to restart Firefox in a normal manner.

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Thanks for your response.What you suggested is what I have been doing,but it gets a little tiring when you have to do that 30-40 times a day.There must be a way to solve this problem.I think it all started when I updated to Firefox 4 Thanks again

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Chosen Solution

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Thank you.I think you may have solved my problem.It seems that Spybot S&D was the culprit

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I don't have this problem as long as I leave one Firefox instance open. It only happens when I close the last instance. I think it is related to the way firefox handles tabs which I do not use. The designers want you to leave Firefox running all the time and just open and close tabe.