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After a major update to Windows 10 yesterday Firefox won't start with an error message about msvcp140.dll having an error. I reinstalled Firefox but it didn't f

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After a major update to Windows 10 yesterday Firefox won't start with an error message about msvcp140.dll having an error. I reinstalled Firefox but it didn't fix it. Error status 0xc000012f.

After a major update to Windows 10 yesterday Firefox won't start with an error message about msvcp140.dll having an error. I reinstalled Firefox but it didn't fix it. Error status 0xc000012f.

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You can check if you only have one copy of msvcp140.dll and not possible older versions.

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All Replies (4)

msvcp140.dll = Microsoft® Visual Studio

Run the Windows updater again.

Reboot the computer.

Ɖɔɖɔɖo si wotia

You can check if you only have one copy of msvcp140.dll and not possible older versions.

I had to download a new copy of the dll file and copy it over to System32 in Windows.

kemp.roger said

I had to download a new copy of the dll file and copy it over to System32 in Windows.