This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Won't Open

  • 2 replies
  • 0 have this problem
  • 2 views
  • Last reply by cor-el

more options

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.

All Replies (2)

more options

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.


more options

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