Really necessary to wipe my hard drive clean with dban, and reinstall everything? Received a strange email(Said Xfinity, than said unknown, than it disappeared), and a fried said I needed to wipe my hard drive with dban and reinstall everything, they claimed I can get viruses that most software can't detect and that their are always new viruses that can't be caught. I never opened the email, and did a full system scan with Norton, Malewarebytes and superantispyware and they all found nothing except a few tracking cookies.