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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

kemp.roger
kemp.roger
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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.

Chosen solution

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

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FredMcD
FredMcD
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msvcp140.dll = Microsoft® Visual Studio

Run the Windows updater again.

Reboot the computer.

cor-el
cor-el
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Chosen Solution

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

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

Paola Gatti
Paola Gatti
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kemp.roger said
I had to download a new copy of the dll file and copy it over to System32 in Windows.