Hi
If you haven't already then you can open Windows Powershell Windows Key Plus X or (right click the Start Button) and select...
Windows Powershell (Admin)
In the command line type...
SFC /scannow
See if it finds anything, some things it will fix, if it finds them.
Next try the same procedure and type
DISM /Online /Cleanup-Image /RestoreHealth.
That's a place to start anyway.
Note the spaces before the forward slants /
If nothing else works it may come to backing up your data and reinstalling Windows but start here.
Mike