JSI Tip 9632. When you split a mirrored volume in Windows 2000, the partition type of one of the volumes changes?

When you use Disk Management (Diskmgmt.msc) and press Break Mirror, randomly one of the volumes will be set to partition type 0x6 (PARTITION_HUGE) and the other volume will retain its' original type, like 0x7 (PARTITION_IFS).

To workaround this problem, right-click the disk that you don't need and press Remove Mirror.