Step 2: Restore a Deleted Active Directory Object

When Active Directory objects are deleted, they are placed in the Deleted Objects container. By default, the CN=Deleted Objects container is not displayed. You can use the Ldp.exe administration tool in Active Directory Domain Services (AD DS) to display the Deleted Objects container.

Membership in Domain Admins, or equivalent, is the minimum required to complete this procedure. Review details about using the appropriate accounts and group memberships at Local and Domain Default Groups (http://go.microsoft.com/fwlink/?LinkId=83477).

To display the Deleted Objects container

You can use Ldp.exe to restore a single, deleted Active Directory object.

Important
You have to run Ldp.exe from an elevated command prompt to restore a deleted object.

Membership in Domain Admins, or equivalent, is the minimum required to complete this procedure. Review details about using the appropriate accounts and group memberships at Local and Domain Default Groups (http://go.microsoft.com/fwlink/?LinkId=83477).

To restore a deleted Active Directory object using Ldp.exe

Note

When you delete or recover an Active Directory object with link-valued attributes, AD DS must process the object’s link value table to maintain referential integrity on the linked attribute’s values. Because deleting or recovering an Active Directory object results in modifications to the object’s link value table, if you attempt to delete or recover an object during its ongoing link-value-table processing time, the operation will be blocked. For example, if you use the Active Directory Recycle Bin to recover a deleted object with a large number of link-valued attributes (for example, a group object with 10 million users) immediately after it was deleted (or anytime throughout the duration of its link-value-table processing), the object recovery will be blocked. (If you are using Ldp.exe to perform the recovery, you might see the following error message: "Error 0x2093 The operation cannot continue because the object is in the process of being removed.")

You can also restore a deleted Active Directory object by using the Get-ADObject and Restore-ADObject Active Directory module for Windows PowerShell cmdlets. The recommended approach is to use the Get-ADObject cmdlet to retrieve the deleted object and then pass that object through the pipeline to the Restore-ADObject cmdlet.

To restore a single, deleted Active Directory object using the Get-ADObject and Restore-ADObject cmdlets

For more information about the Get-ADObject and Restore-ADObject cmdlets, at the Active Directory module for Windows PowerShell command prompt, type Get-Help Get-ADObject or Get-Help Restore-ADObject, and then press ENTER.

Consider the following scenario: An administrator at Contoso.com accidentally deletes a nested organizational unit (OU) called Finance_Department, which contains user accounts for employees in the Finance department. The administrator deletes another OU called Admins, which contains user accounts for administrative assistants that work for the Finance department. Brian and Mary are user accounts in the Finance_Department OU. Tom is a user account in the Admins OU. The following illustration shows the Finance_Department OU.

When the Finance_Department OU is deleted, all its objects (a total of five objects) are moved to the Deleted Objects container, with their distinguished names mangled. The Deleted Objects container displays all logically deleted objects in a flat hierarchy as its direct children. The recommended approach to restoring a nested OU to its original state is to use the Get-ADObject Active Directory module cmdlet to retrieve the deleted objects one hierarchy level at a time and then to pass those objects through the pipeline to the Restore-ADObject cmdlet. If the administrator is not familiar with the original hierarchy of the Finance_Department OU, the administrator must first use the Get-ADOBject cmdlet to perform several investigation steps:

• For example, the administrator decides to search for the user account Mary with the Get-ADOBject cmdlet, using the msDS-lastKnownRDN attribute in the ldapFilter parameter and constructing the command so that the lastKnownParent attribute of Mary is returned, as follows:
  
  Get-ADObject -SearchBase "CN=Deleted Objects,DC=contoso,DC=com" -ldapFilter:"(msDs-lastKnownRDN=Mary)" –IncludeDeletedObjects –Properties lastKnownParent
  
  In the output that the Get-ADObject cmdlet returns, the administrator notices that the value for lastKnownParent of Mary is Finance_Department. The administrator also notices that the distinguished name of the Finance_Department OU is mangled, which indicates that the Finance_Department OU object itself is deleted. (An example of a mangled distinguished name is OU=Finance_Department\0ADEL:e954edda-db8c-41be-bbbd-599bef5a5f2a,CN=Deleted Objects,DC=contoso,DC=com.)
  
  
• The administrator then decides to search for all the objects in the Deleted Objects container whose lastKnownParent value is Finance_Department, using the following command:
  
  Get-ADObject –SearchBase "CN=Deleted Objects,DC=contoso,DC=com" -Filter {lastKnownParent -eq 'OU=Finance_Department\\0ADEL:e954edda-db8c-41be-bbbd-599bef5a5f2a,CN=Deleted Objects,DC=contoso,DC=com'} -IncludeDeletedObjects -Properties lastKnownParent | ft
  
  

  Note
  Make sure that you escape the slash (\) in the mangled distinguished name that is used in the Get-ADObject cmdlet with another slash.

  In the output that the Get-ADObject cmdlet returns, the administrator notices that Admins is an OU itself.
  
  
• The administer further searches for all the deleted objects with a lastKnownParent attribute equal to Admins, using the following command:
  
  Get-ADObject –SearchBase "CN=Deleted Objects,DC=contoso,DC=com" -Filter {lastKnownParent -eq 'OU=Admins\\0ADEL:6b405c87-027c-4135-95af-36c31002be5a,CN=Deleted Objects,DC=contoso,DC=com'} -IncludeDeletedObjects -Properties lastKnownParent | ft
  
  

  Note
  Make sure that you escape the slash (\) in the mangled distinguished name that is used in the Get-ADObject cmdlet with another slash.

  In the output that the Get-ADObject cmdlet returns, the administrator finds the user account Tom.
  
  
• In Windows Server 2008 R2, deleted nested objects must be restored from the highest level of their hierarchy to a live parent. Therefore, the Finance_Department OU object must be restored first. Because all previous investigation steps were performed using the lastKnownParent attribute, which points to the direct parent of the object and does not indicate whether the next parent object is also deleted, as a check the administrator can verify that the value of lastKnownParent for Finance_Department is indeed a live OU by running the following command:
  
  Get-ADObject -SearchBase "CN=Deleted Objects,DC=contoso,DC=com" -ldapFilter:"(msDs-lastKnownRDN=Finance_Department)" –IncludeDeletedObjects –Properties lastKnownParent
  
  This concludes the investigation and the administrator is ready to restore the Finance_Department OU to its original hierarchy and state.
  
  

Important
It is critical to begin restoring objects from the highest level of the hierarchy because deleted objects must be restored to a live parent.

To restore the Finance_Department OU, the administrator can perform the following procedure.

To restore the Finance_Department OU

For more information about the Get-ADObject and Restore-ADObject cmdlets, at the Active Directory Module for Windows PowerShell command prompt, type Get-Help Get-ADObject or Get-Help Restore-ADObject.

For a sample Windows PowerShell script that you can use to restore a deleted tree of Active Directory objects, see Appendix B: Restore Multiple, Deleted Active Directory Objects (Sample Script).