This could also be a Windows corruption issue.
Open a CMD window as Administrator then type
SFC /SCANNOW
That will seek out any corrupt, deleted or wrong version files in your Windows Install automatically. When completed reboot and give it another go. I've found it fixes issues regularly.
If it does not find anything wrong, then a malware check is a good thing to try.
Ohh I'll give that a go...
Pretty well protected but you never know..
Thanks.