No McAfee is a pay to use. if your after a free AV, use Microsoft Security Essentials, or AVG Free, Avast Free.
I have 2 Anti virus products that my experience tells me not to touch. Macafee is one of them. Microsoft security essentials is one of the better free AV's in my experience and has yet to let me down across 5 PC's used by various family members. I have a neighbor who is a friend of my wife who used to come around once every couple of months with an issue that someone else in the house had caused(always is isn't it) Anyway I have yet to hear from them after installing and setting up MSE.