New
#1
Windows Key + x should give you a menu with multiple entries, including Command Prompt and Command Prompt (Admin).
Still didn't work.
Booted to Safe Mode and ran
Dism /Online /Cleanup-Image /StartComponentCleanup
Dism /Online /Cleanup-Image /RestoreHealth
SFC /scannow
All ran clean, no errors. Booted normally and Commadn Prompt is working fine again.
No idea what happened.