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Won't Open

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  • Last reply by cor-el

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All of a sudden, I can't open Mozilla Firefox. I uninstalled and reinstalled the program. I am on Windows 10. I still cannot open Mozilla even through the icon is on my desktop. I have turned off my computer and turned it back on. I still cannot open the program.

All of a sudden, I can't open Mozilla Firefox. I uninstalled and reinstalled the program. I am on Windows 10. I still cannot open Mozilla even through the icon is on my desktop. I have turned off my computer and turned it back on. I still cannot open the program.

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Did you recently uninstall an application that was using Visual C+ runtime components?

You can check for issues caused by a corrupted or incomplete Visual C++ installation that is missing runtime components (Redistributable Packages) required by Firefox, especially VCRUNTIME140_1.dll.

See "Visual Studio 2015, 2017, 2019, and 2022":

You may also have to install the Visual Studio 2013 Redistributable Package. You need to reboot the computer.


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Try to start Firefox in Troubleshoot Mode to see if that works.

  • Windows: hold down the Shift key while starting Firefox
  • Mac: hold down the Options key while starting Firefox