DiskPart.exe is a text-mode command line tool interpreter which enables storage objects such as disks, partitions or volumes configuration and management from a script, remote session, or direct input from a command prompt. DiskPart is actually the underlying utility that augments the Disk Administrator graphical user interface and enables a superset of the actions that are supported by the Disk Management snap-in. The Disk Management snap-in prohibits you from inadvertently performing actions that may result in data loss, sometimes it is recommended that DiskPart is used to enable explicit control of partitions and volumes.
If you need DiskPart for Windows XP, Windows 2003 or Windows 2000 (DiskPart comes built-in with new Windows operating system since Windows Vista, you can download DiskPart.exe from Microsoft Download Center (link dead).
Alternatively, download diskpart_setup.exe from this direct download link: diskpart_setup.exe.
DiskPart works on Windows 2000, Windows 2003 and Windows XP.