Diskpart.exe to extend a data volume in Windows Server
How to use Diskpart.exe to extend a data volume in Windows Server 2003, in Windows XP, and in Windows 2000
You can use the Diskpart.exe utility to manage disks, partitions, and volumes from a command-line interface. You can use Diskpart.exe on both Basic disks and Dynamic disks. If an NTFS volume resides on a hardware RAID 5 container that can add space to the container, you can extend the NTFS Volume with Diskpart.exe while the disk remains a Basic disk.
