I'm using Windows Server 2003 and I have two identical 1TB disks. 1 of them has the operating system partition, the other disk has no partitions. The second disk with no partitions will convert to a dynamic disk without problem, but the one with the OS won't do anything. I right click on it in disk management and choose "convert to dynamic disk" (it's not greyed out) and it ask me which disk I want to convert, I choose the disk, hit ok, and nothing happens. No events logged that I can find.
What would cause this behavior and how can I convert it?