I created a volume/partition using DiskUtility. I did not encrypt or pass protect it. Now I do want to create an encrypted volume in place of this one. So I try to erase this original volume using DiskUtility>erase and I get the message :"erase failed because the disk cannot be unmounted" Huh? The volume was never really mounted or unmounted or I guess its more accurate to say it always mounted automatically on boot along with the main volume that contains the OS and major apps. So what to do now? Do I have to reconfigure the volume so it can be unmounted somehow, then erase it, then create a new volume(encrypted) in its place? If so, how the hell does this newbie do that? Thanks