I am having a problem with Poser 6 in the last few days. It shut itself down in the middle of a scene I was working on, and since then every time I try to start it, it shuts itself down immediately once it gets past the welcome screen. I've reinstalled and reinstalled the service pack, rebooted over and over, done a virus scan, everything I can think of, but it just won't start up! My machine has a decent video card, and I have 1.5GB of RAM, so I know it's not a memory issue. Does anyone know what could be causing this?

Thanks in advance for any help!