ProtectKeyWithAdSid method of the Win32_EncryptableVolume class

Article
01/07/2021

The ProtectKeyWithAdSid method of the Win32_EncryptableVolume class secures the volume's encryption key by using a Active Directory security identifier (SID).

Syntax

uint32 ProtectKeyWithAdSid(
  [in, optional] string FriendlyName,
  [in]           string SidString,
  [in]           uint32 Flags,
  [out]          string VolumeKeyProtectorID
);

Parameters

FriendlyName [in, optional]

A string that specifies a user-assigned identifier for this key protector. If this parameter is not specified, a blank value is used.

SidString [in]

String that contains the Active Directory SID used to protect the encryption key.

Flags [in]

Flags that change the function behavior. This can be one of the following values.

Value	Meaning
FVE_DPAPI_NG_FLAG_NONE 0x0000	No effect.
FVE_DPAPI_NG_FLAG_UNLOCK_AS_SERVICE_ACCOUNT 0x0001	Specifies that the SID-based protector was protected to a service account. If this flag is specified, the caller should ensure that it is running as the appropriate service account before calling UnlockWithAdSid (by temporarily dropping impersonation, for example).

VolumeKeyProtectorID [out]

A unique identifier associated with the created protector. You can use this string to manage the key protector.

If the drive supports hardware encryption and BitLocker has not taken band ownership, the ID string is set to "BitLocker" and the key protector is written to per band metadata.

Return value

This method returns one of the following codes or another error code if it fails.

Return code/value	Description
S_OK 0 (0x0)	The method was successful.

Remarks

Managed Object Format (MOF) files contain the definitions for Windows Management Instrumentation (WMI) classes. MOF files are not installed as part of the Windows SDK. They are installed on the server when you add the associated role by using the Server Manager. For more information about MOF files, see Managed Object Format (MOF)

By default, you cannot add an Active Directory account or group protector remotely. You must enable constrained delegation on the domain controller and source computer. On the domain controller, perform the following steps:

Open Server Manager
Select Computers in Active Directory roles
Select the target client computer and right click
Select the Delegation tab
Select the "Trust this computer for delegation to specified services only" radio button
Select the "Use Kerberos only" radio button
Click Add
Select "Users or Computers"
Select host/ as the Service Principal Name

Perform steps 3 through 9 on the source computer.

Requirements

Requirement	Value
Minimum supported client	Windows 8 Enterprise, Windows 8 Pro [desktop apps only]
Minimum supported server	Windows Server 2012 [desktop apps only]
Namespace	Root\CIMV2\Security\MicrosoftVolumeEncryption
MOF	Win32_encryptablevolume.mof