PGP Whole Disk Encryption 9.9 is a client software application that provides whole disk encryption as part of PGP’s suite of encryption products. It secures the entire hard drive and is available on a wide variety of platforms, including 32-bit and 64-bit versions of Windows 2003, XP, Vista and Mac OS X. It can be installed as a standalone but is most often managed by the PGP Universal Gateway, which manages the keys and other enterprise aspects of the platform.