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Firefox will not open. Unable to uninstall because message says Firefox is running. How do I turn it off?

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  • Last reply by cor-el

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I upgraded Firefox after upgrading to windows 8.1 now firefox will not open but when I try to uninstall the program I get a popup telling me to close firefox. The task manager says nothing is running. Help.

I upgraded Firefox after upgrading to windows 8.1 now firefox will not open but when I try to uninstall the program I get a popup telling me to close firefox. The task manager says nothing is running. Help.

All Replies (2)

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Try restart your computer then try unistall, then get the most recent version here:

Also:

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Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.