Detecting and Removing a Windows Snapshot Partition

If a request to add, encrypt, or extend a Windows disk (hcl add, hcl encrypt, or hcl extend) fails with an error stating there are too many partitions on the disk, the problem may be that Windows added a Snapshot partition at the beginning of the disk. If the Windows Disk Manager shows only two partitions, excluding the Microsoft Reserved Partition and the KeyControl private partition, use this procedure to see if there is a hidden Snapshot partition on the disk.

  1. Log into the VM as a System Administrator and open a Command Prompt or start Windows PowerShell.

  2. Determine the disk # of the drive letter using one of the following methods: 

    • Using the KeyControl Policy Agent: run hcl status

    • Using the Windows Disk Manager: run diskmgmt.msc

    Running one of these commands will display the disk number of the drive letter that you want to use.

  3. Enter the command diskpart.
  4. At the DISKPART prompt, enter the command select Disk disk-number, where disk-number is the number of the Windows disk that you want to check.

  5. Enter the command list partition.

    If there is a Snapshot partition, it typically starts at offset 273 KB. For example:

    DISKPART> list partition

Partition ### Type             Size    Offset
------------- ---------------- ------- -------
Partition  4  Unknown          256 KB  273 KB
Partition  2  Reserved         31 MB   529 KB
Partition  3  Primary          300 MB  32 MB
Partition  1  Unknown          10 MB   332 MB

  6. To verify that the partition is a Snapshot partition, enter the command select partition partition-number, where partition-number is the number of the partition you want to check. For example:

    DISKPART> select partition 4

  7. Enter the command detail partition. If this is a Snapshot partition, the type will be listed as caddebf1-4400-4de8-b103-12117dcf3ccf. For example:

    DISKPART> detail partition
Partition 4
Type : caddebf1-4400-4de8-b103-12117dcf3ccf
Hidden : Yes
Required: No
Attrib : 0000000000000000
Offset in Bytes: 279552

  8. To delete the Snapshot partition, enter the command delete partition.

  9. Repeat the select partition and detail partition commands for each partition on this disk, but ensure that you only delete partitions where the Type matches the value caddebf1-4400-4de8-b103-12117dcf3ccf.

    The type caddebf1-4400-4de8-b103-12117dcf3ccf indicates that this is a Microsoft snapshot, which was only used when Microsoft VSS created it, and is no longer used. Microsoft VSS will create a new snapshot when necessary.

  10. Resubmit the hcl add, hcl encrypt, or hcl extend request.