Use Bitdefender or Kaspersky free anti-virus instead.
Open a terminal as administrator ( right click the terminal (cmd) and choose open as administrator ):
type sfc /scannow
sfc stand for sys file check so it should fix your problem. If not try :
DISM /Online /Cleanup-image /Restorehealth
If it fails, backup your stuff and do a fresh Reinstall.
Search Freemediaheckyeah brother. Become free from the lie of untrustworthiness of cracked software. Follow the ship and be a fellow cremate. freedom becons.