I have used Norton Antiviris and Firewall now for two years and am a very satisfied customer. It has stopped a number of intruders, and let me follow them back to their origin. Mostly they come from India, of all places. Have had no problems with it, installed nicely and runs great. Although on full scan of the whole computer, takes 100 percent of the PC most of the time. Cannot do much else while a full scan is on.