I'm running the download version of Creator 2009 on a Vista Home Premium x64 machine. Glitch-free installation process and (so far) no bugs at all when running the various modules. As someone who has lived with the ups and downs of "Creator" for many years (dating way back to the early Adaptec days) I was actually "anticipating" problems with Vista x64 but to my amazement, so far so good. I'm also running several other editing/burning apps, some of which use "Gear" and "Goldenhawk" drivers with no Roxio conflicts whatsoever. So Creator 2009 is definitely capable of running properly in the Vista x64 environment and even seems more robust and tolerant than previous versions. Pure speculation, but my initial suspicions would lean towards needed Vista services, processes, and/or libraries that might be corrupt, disabled, or missing. BTW, have you tried uninstalling .net 3.5 and then reinstalling Creator, allowing Roxio to initiate the .net 3.5 installation?