Look at AVG. I have the network edition and, although I am not sure I really know all the bells and whistles, I managed to install it on my server and push it out to the clients and I am a computer idiot. But it is much better, IMO, than McAfee or Nortons which overtake your system. I tried Nortons and everything slowed down so it was awful. Then when you try to uninstall it is like trying to get rid of ants in your house. The little b@#$%&ds are everywhere!