I have a 1Ghz Ath 133FSB, 512Mb SDram, win98SE. Poser4 with PPP Sr3 I have see this happen myself, pulling memory didn't help me. Disk cashing is set to server, windows assigned swap file. I found it happens to me if i do a bunch of quick renders one after another,(like when I an making a new character, and or making a very complex scene (20 or more figures and props with high res textures and more than 4 lights.) what I do is do what I'm doing and in the case of a character save it in the lib and as a PZ3. then reboot the system. Or in the case of a complex shot I do much the same except I render less and save more. also I found if I have a light selected and render a buch it will lock up more often,( I suspect it is the shadow map rendering that hangs it.) I have also poser poser in equal and lesser system running win2K , ME ans XP (home and pro) and found this effect to continue un-abated.