mz I dont use Norton anymore as it uses too much memory. I use AVG and its free. Havent had a problem since I started using it and thats been a couple of years. If you need to restore your computer to a date when it was running correctly here is some help if you are running XP.
Go to programs-accessories-system tools-system restore. When you get to system restore just pick a date that you remember that everything worked correctly. PL