I've just gotten Parallels installed / newbie to using it and I've been getting a greyed-out window that doesn't allow me to do anything except shut it down and restart. What causes this?
Do you have the latest version of Parallels (3188). The reason I ask is that earlier versions of Parallels did not support the Core 2 Duo Processor. You can download the current version from the Parallels web site, and your existing product key should still work. Also, have you installed and operating system in your Virtual Machine? If so which one?