If you have to reinstall the OS of your PC to keep it running, consider installing GNU/Linux to stop the foolishness.
There you have it. Anti-malware cannot fix that other OS. You need to re-install/restore from a backup. It’s easier to install GNU/Linux if you don’t have a backup. Check out Debian GNU/Linux or one of my videos:
Just choose “Install” and choose “desktop” and “standard system” when choice of installations comes up. Takes 10-15 minutes from a CD or an hour or less from the web with a broadband connection for a newbie on a newish machine. That other OS can take hours, even on a new machine.