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Firefox instantly closes after opening it

  • 3 réponses
  • 0 a ce problème
  • 25 vues
  • Dernière réponse par zeroknight

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As described in the title Firefox instantly closes after opening it. I can see the window opening for half a second but then it closes again. Same with Troubleshoot mode. New installation of Windows 11, new installation of Firefox, only the standard antivirus from Windows. I don't know what could pose an issue except maybe some corrupt data that was downloaded from Onedrive although I already deleted the profiles in the AppData folder.

As described in the title Firefox instantly closes after opening it. I can see the window opening for half a second but then it closes again. Same with Troubleshoot mode. New installation of Windows 11, new installation of Firefox, only the standard antivirus from Windows. I don't know what could pose an issue except maybe some corrupt data that was downloaded from Onedrive although I already deleted the profiles in the AppData folder.

Toutes les réponses (3)

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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":

Download the latest vc_redist.x64 and vc_redist.x86 files.

You need to reboot the computer.


Boot the computer into Windows Safe Mode with network support to see if that has effect.

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Thank you for your answer. I installed the packages. Firefox still didn't start. However, in Safe Mode Firefox seems to operate normally. Any ideas on why that is the case / how to fix it? I never had an issue like this before.

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It sounds like your Microsoft account has parental controls enabled which limits what browsers you can use, you could try to get this limitation removed or create a new account. Renaming firefox.exe to something else can get it working but this will break DRM protected videos.