running vista home Sp2. Valid OS. Defender is running and picking up a few 100 viruses and malware infected files. I dont believe theyre all infected. If let defender run and clean up the files, then reboot, I cant login as once I enter user/pass I get a message saying my copy of windows isnt genuine. I have to boot in safe mode and restore back to before I let defender do its stuff so it definitely knocking out something. I'll happily not let defender clean up but Im now worried i have a virus/malware. what to do?