I haven't used an anti virus in like a year now because of my operating system not being really all that venerable to them. But when I am called over to my certain operating system friends house. I normally try to use what ever anti virus that comes on there computer normally it is Norton or Macfee(SP?). I generally give that a run then I install Spybot Search & Destroy then Adaware. Finally after I run those two I use my favorite and in my unprofessional opinion Housecall by TrendMicro. It is a computer saver.