I only Norton product I use is the internet security thing. I am bad at doing regular defrags, its just the down time for me to defrag 19gigs that makes me keep putting it off. Even if we knew approximately how much space we should make sure is free to avoid the problem would be good. If I knew that poser needed 2gigs to work with while rendering I would be able to make sure that is always available, but I have no idea how much poser wants :)P