Cause of this error
Games and softwares that are build using Microsoft Visual Studio require some sort of supporting libraries for them to run on the machine. These files are called DLL and our games are often dependent on these libraries.
If these files are not installed on your system, games like Witcher 3: Wild Hunt will prompt an error with code 0xc000007b. You will need to download and install these necessary DLL files in order to run Witcher 3.
Witcher 3 error 0xc000007b fix
Step 1: Visit this link https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads to download these library files installer.
Step 3: After that visit this link https://support.microsoft.com/en-us/help/4032938/update-for-visual-c-2013-redistributable-package
Step 4: Download both vcredist_x64.exe and vcredist_x86.exe files according to your language pack.
Step 5: Now visit this link https://www.microsoft.com/en-in/download/details.aspx?id=30679 and click on the download button to download the installer.
Step 6: Don’t forget to download both x86 and x64 files and also to run all of the downloaded installers and finish the installation.
Step 7: Restart the computer and see if the game runs.
Step 8: If this doesn’t work for you you can try updating your Windows and graphics drivers. That will do the work. You don’t need to reinstall windows or reinstall the game again.