I renewed my subscription a month or 2 ago, and the other day I realized Norton was no longer coming on automatically at start-up. When I try opening the program from the Start menu, I get a Norton error message 8504, 104. I read some similar threads that advised uninstalling and reinstalling the software, but it came pre-installed on my Sony Vaio with a free trial, so I don't have a physical copy. Any suggestons? Thanks.