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can't open or close mozilla firefox

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  • 1 has this problem
  • 13 views
  • Last reply by FredMcD

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After we downloaded Windows 10 I haven't been able to open Mozilla firefox. I went to control panel to uninstall and reinstall but when i clicked uninstall a message came up that said I must first close mozilla firefox before uninstalling. I can't close it cuz I can't open.

After we downloaded Windows 10 I haven't been able to open Mozilla firefox. I went to control panel to uninstall and reinstall but when i clicked uninstall a message came up that said I must first close mozilla firefox before uninstalling. I can't close it cuz I can't open.

All Replies (2)

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


You can also check for issue with Microsoft Family Safety on Windows 10. http://windows.microsoft.com/en-us/windows-10/turn-off-microsoft-family-settings

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Do you have the Firefox icon on your quick launch? Right click on it, and select Open New Window. Sometimes this works. If it opens, close it by Menu > File > Exit.


This is not a cure but will make it easier if Firefox locks up in Windows. https://support.mozilla.org/questions/997866 {web link}