Try Malwarebytes (free edition).
I got a virus, one of those fake anti-virus ones... it was a borrowed computer. I downloaded something to kill it but it also killed some important files in the PC. I really bungled that one.
It wouldn’t let me add Malware Bytes, it should have been there before it.
Malwarebytes is excellent for cleaning up. For running protection, get rid of the heavy dinosaurs like Kaspersky, Symantec and the others and go with Avast.