I find big programs like Norton and McAfee seem to take over your computer and make alot of problems for many users,They use alot of computer memory and there are free programs out there to download on the net that dont take up lots of your computers memory. Try Avira anti virus and spybot search and destroy,they do just as good but don't take over your computer! I'v used them for years and never had problems on my pc,aslong as you keep them updated and scan often they keep your pc running great!