mcafae = crap.
All free AV programs are crap.
The only AV programs worth anything at all are Symantec Corporate,Norton and E-Eye.
Eeye is written by a person who broke into government and banking websites around the world...got busted while under age and now has his AV program used by UCLA,Airlines (protects aircraft flight/navigation computters),Federal Reserve Bank,government enities and others who want top end protection.
Eeye is really slow to scan but anything it does not know is put into and run inside a sandbox for inspection.
An AV program written by a true hacker to stop hackers.
http://www.eeye.com/Home.aspx