When trying to encrypt a disk with Symantec Drive Encryption (formerly known as PGP Whole Disk Encryption), the fails and the following error appears:
This Disk Does not appear to have a valid volume.
PGP Whole Disk can only encrypt disks with at least one valid volume.
Refer to article TECH203071 for more details and requirements on UEFI support and Symantec Drive Encryption.
HP Elite Book 8560W
Windows 7 64-bit