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Unable to open Firefox

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  • Last reply by Jan

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Suddenly on Friday afternoon I could no longer log in to Firefox (or any of the 365 Office products) - almost like permissions were somehow changed. Some of my software works just fine. I downloaded and installed Firefox again; same for 365 Office and Windows 11. I ran all the repairs I could find in Windows and on the Internet. Now I can get into the various 365 Office products but only by running as administrator (right click and choose Run as Admin) - the clicking on icons does not work. I still cannot open Firefox. The other thing is that I can open MS Edge just fine just by clicking on the icon (what I'm using here) only I really don't want to use it. Does anyone have any ideas? Thanks! Jan Mogensen

Suddenly on Friday afternoon I could no longer log in to Firefox (or any of the 365 Office products) - almost like permissions were somehow changed. Some of my software works just fine. I downloaded and installed Firefox again; same for 365 Office and Windows 11. I ran all the repairs I could find in Windows and on the Internet. Now I can get into the various 365 Office products but only by running as administrator (right click and choose Run as Admin) - the clicking on icons does not work. I still cannot open Firefox. The other thing is that I can open MS Edge just fine just by clicking on the icon (what I'm using here) only I really don't want to use it. Does anyone have any ideas? Thanks! Jan Mogensen

All Replies (2)

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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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Hi cor-el: Thanks for your reply and I'm fairly certain I did just as you say: I clicked on the uninstall that deleted Visual C+ files. I followed the links you provided but unfortunately, I'm not sure how to install these files so they can be used. Maybe you can help with this? Thanks!! Jan