On 2 o3 occasions Norton Internet Security disappears completely from the task bar and Windows brings up a warning there is no Firewall running. This happened once while I was doing something else in another room. So could have been without Firewall for over an hour!
Also have had the recurring problem "Symantic Framework has to close" message.
Have re-installed Norton a couple of times last year because of similar problems. This product ain't what it used to be!