I had an experience that may help. I have Poser 8, never had any trouble with it, then got a virus, cleared it all out, but the residual was that my P8 was now very unstable and would crash on renders it used to fly through. After trying everything with no luck, by chance, I right-clicked on the program icon and checked under properties - under compataility - and it was set to be compatiable with Windows Vista. I changed it to Windows 7, and now everything is fine.