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Error Code prevents access.

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  • Last reply by cor-el

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Have had Firefox for years. Got error code Oxc000012f. Unable to access Firefox. Please help.

Have had Firefox for years. Got error code Oxc000012f. Unable to access Firefox. Please help.

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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":

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

You need to reboot the computer.