Personally i'd get rid of Norton right away and use something like Windows Live Onecare. If the problem is Norton, best to try and Unistall it first and see if the problem happens again, if not then it's obviously Norton.
However i recently had a similar problem which happened now and again and i replaced my CPU and Fan unit and have had no problems in over 3 months, or even if you have added more memory that could cause the problem too if it's the wrong voltage. Best to narrow it down and see by Uninstalling Norton anyway, personally i'd never use Norton again.
Andy, February 2009
