I think your 2GB of RAM may be the problem. That amount of physical memory was unheard of when Poser 4 was conceived. I know the others have mentioned it, but I'll risk repeating it here - just ignore me if you already tried this. From memory, there is/was a memory updater in addition to the 4.03 updgrade, and I think you need that too. Unfortunately I couldn't find it at Sith Micro, but I couldn't find the 4.03 updater either so that must be a reflection on my searching skills. ;)