over 2 years ago - AndrewT - Direct link
In the game launcher please set Display mode to windowed.THEN go here:
support.microsoft.com

Latest supported Visual C++ Redistributable downloads

This article lists the download links for the latest versions of Visual C++ Redistributable packages. support.microsoft.com And run the x86 and x64 installers there.

If those don't help:

Please attach here your Documents/Paradox Interactive/CK3/pdx_settings.txt .
From your Documents/Paradox Interactive/CK3/logs/ folder, attach here system.log , error.log, exceptions.log