GUID Partition Table (GPT) is a partitioning scheme that is part of the Unified Extensible Firmware Interface specification; it uses a globally unique identifier for qualifying devices. It is the next generation partitioning scheme designed to succeed the Master Boot Record partitioning scheme method.
Disk Management describes disks with the GUID partition table (GPT) partitioning style as GPT disks and disks with the master boot record (MBR) partitioning style as MBR disks. You can perform the same tasks on GPT disks as you can on MBR disks with the following exceptions:
Our new Expansion drives come out of the box partitioned GPT, but our older line of Expansion drives came partitioned out of the box MBR; there was no size limitation with any operating system, even Windows XP. We were able to do this because these drives came with 4K sector sizes and a special bridge card installed on them to get past the 2.2TB limitation. We stopped manufacturing these drives this way, because Windows XP is no longer a supported operating system, additionally the current Expansion drives enable Windows 7 users to use them with the Windows 7 Image Backup program.
Here are pictures of the new models of Expansion drives that are not supported on the Windows XP operating system.
Here are pictures of the older models of Expansion drives that are supported on the Windows XP operating system.