Updated: April 17, 2012
Applies To: Windows 7, Windows Server 2008, Windows Server 2008 R2, Windows Vista
On basic disks, marks the partition with focus as active.
|DiskPart verifies only that the partition is capable of containing the operating system startup files. DiskPart does not check the contents of the partition. If you mistakenly mark a partition as active and it does not contain the operating system startup files, your computer might not start.|
This informs the basic input/output system (BIOS) or Extensible Firmware Interface (EFI) that the partition or volume is a valid system partition or system volume.
Only partitions can be marked as active.
A partition must be selected for this operation to succeed. Use the select partition command to select a partition and shift the focus to it.