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Firefox will not open after multiple reinstalls and deleting all data.

  • 2 cavab
  • 1 has this problem
  • 3 views
  • Last reply by vagemedal

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I had firefox on my computer a long time ago but uninstalled it. I reinstalled it and it will not open. I did a refresh and it would not work. I went through and deleted the following folders to no avail upon fresh install from https://www.mozilla.org/en-US/firefox/new/

Deleted folders: AppData/Local/Mozilla AppData/LocalLow/Mozilla AppData/Roaming/Mozilla Program Files/Mozilla Firefox ProgramData/Mozilla

Upon fresh installs trying to boot into safe mode results in a window briefly flashing in the taskbar and closing immediately. There's no message or anything asking if I want to boot it into safe mode. I don't care about keeping previous data for Firefox like profiles or bookmarks. I do not know what else to do.

I had firefox on my computer a long time ago but uninstalled it. I reinstalled it and it will not open. I did a refresh and it would not work. I went through and deleted the following folders to no avail upon fresh install from https://www.mozilla.org/en-US/firefox/new/ Deleted folders: AppData/Local/Mozilla AppData/LocalLow/Mozilla AppData/Roaming/Mozilla Program Files/Mozilla Firefox ProgramData/Mozilla Upon fresh installs trying to boot into safe mode results in a window briefly flashing in the taskbar and closing immediately. There's no message or anything asking if I want to boot it into safe mode. I don't care about keeping previous data for Firefox like profiles or bookmarks. I do not know what else to do.

All Replies (2)

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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 and 2019":

You may not need the latter (32-bit version) if you use 64-bit Firefox. You may have to reboot the computer.

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This made some progress. I was able to open firefox for about 15 sec (seemed to be normal) and then it autoclosed. After restart, it was the same. Reinstalling it again and somehow back to square 1.