Anyone else seen this? Part modeled in SWx2004, SP1, and opens fine on systems with SP1. Try to open it on a system with SWx2004, SP0 and I get an 'unable to obtian the required memory' error. Same error on two different computers, both with way more horsepower than the system with SP1 on it. Upgrade one of those systems to SP1 and the problems go away Just curious if its unique to this file, or if there is a potential backward compatibility problem between service packs (which I don't think I've ever seen before. A feature or three may error out, but never this...) Thanks, Ed