Uhm free antivirus scan site: http://housecall.trendmicro.com
Also, I used to work as tech support my main goal was to get customers off the phone as soon as possible! Which ment telling them anything that would get them off the phone.
Basically you bought their software, its not working how you want it to. So Call McAffe back, tell them what microshaft said, if they start giving you the run around ask for a supervisor til you get the results you want. Thats about all you can do.