I don't know what version of Norton Internet Security you are using but, I was using 2004 and had nothing but trouble until I got rid of it. There is a strong opinion on this forum - including mine - that Norton just does not cut it. I now us eTrust EZ Armor anti virus & Firewall by Computer Associates and have had no problems with viruses or wormns and it takes very little resources. The choice is yours, but, I would get rid of the Norton.
I have a HP pavillion 533w with Norton antivirus, I keep it updated and my windows updated except SP2,I have had this computer about 2 yrs and no problems, lately though when I try to surf at all I can't toggle between differant websites because I get the famous "web page cannot be displayed". As soon as I disable Norton Internet Security,,,everthing works great!I did set my own custom levels for security but I switched back to default and still same Problem.I feel I'm pretty good @ computers I switch Hardware and Software all the time,,,but this has me stumped,,,or just so simple I over looked it. Any Ideas,,Thanks in advance Bill