Just to give everyone a heads up, I have discovered what might be a problem with PowerDVD Ultra version 2911. After backing up the HD DVD movie 'Breach', I tried playing it but PowerDVD would crash, without any error messages, every time it began to play the main feature. I tried another new HD DVD movie and it played ok. Next I tried playing the rip of 'Breach' on another computer and it played without problems, so then I uninstalled and reinstalled PowerDVD Ultra on the problem computer and then the problem went away. Of course it could be a problem with my computer, but because I was able to fix it so easily, I'm speculating that there may be a problem with PowerDVD Ultra that's causing the installation to get corrupted. Of course, since it hasn't happened on any of my other computers, I can't be sure. If anyone else has any experience with this kind of PowerDVD problem I'd like to know.