An application directory partition is a directory partition that is replicated only to specific domain controllers. Application directory partitions are usually created by the applications that use them to store and replicate data. A domain controller that participates in the replication of a particular application directory partition hosts a replica of that partition.
For example, Domain Name System (DNS) application directory partitions are created by default on domain controllers that run Windows Server 2008 R2 if they are also hosting Active Directory–integrated DNS zones. The following DNS application directory partitions are created on these domain controllers:
DomainDNSZones: This application directory partition includes DNS data that is replicated to all domain controllers in the domain.
ForestDNSZones: This application directory partition includes DNS data that is replicated to all domain controllers in the forest.
The Active Directory Domain Services Installation Wizard can remove these DNS application directory partitions when it removes Active Directory Domain Services (AD DS) from the last domain controller that hosts the partitions.
If you are removing the last domain controller in the domain, the wizard lists the distinguished name for the DomainDNSZones application directory partition. If you are removing the last domain controller in the forest, the wizard lists the distinguished name for the ForestDNSZones application directory partition. You can click Next to have the wizard remove these DNS application directory partitions.
Before you delete the last replica of any other application directory partition, identify the applications that use the application directory partition, determine if it is safe to delete the last replica, identify the partition deletion tool that the application provides, and then remove the application directory partition by using the tool that is provided or by using the Ntdsutil command-line tool if no tool is provided.
Identify the applications that use the application directory partition
To determine what application directory partitions are hosted on a computer, refer to the list on the Application Directory Partitions page in the Active Directory Domain Services Installation Wizard. If the list does not provide enough information to identify the applications that use a particular application directory partition, you may be able to identify them in one of the following ways:
Consult a member of the Enterprise Admins group.
Consult network change-control records that your organization maintains.
Use Ldp.exe or the ADSI Edit snap-in to view the data that is contained in the partition.
Determine if it is safe to delete the last replica
Removing the last replica of an application directory partition causes the permanent loss of any data that is contained in the partition. If you have identified the applications that are using the application directory partition, consult the documentation that is provided with those applications to determine if there is any reason to keep the data. If the applications that use the application directory partition are out of service, it is probably safe to remove the partition.
If it is not safe to delete the last replica, or if you cannot determine whether or not it is safe and you must demote the domain controller that holds the last replica of a particular application directory partition, follow these steps:
Add a replica of the partition on another domain controller.
Wait for the contents of the application directory partition to replicate to the domain controller that holds the new replica.
Remove the replica of the partition on the domain controller to be demoted by using the partition management subcommand of Ntdsutil.exe. For more information, see the Ntdsutil partition management topic in Command Reference (
Identify the partition deletion tool that is provided by the application
Most applications that create application directory partitions provide a tool to remove the partitions. When possible, always delete an application directory partition by using the tool that the application provides. For example, to delete a Telephony API (TAPI) partition, use the Tapicfg.exe command-line tool. Refer to an application's documentation for information about removing application directory partitions that the application creates and uses.
If you cannot identify the application that created the application directory partition or if your application does not provide a tool to delete application directory partitions that it created, you can use the Ntdsutil command-line tool. Use the partition management subcommand of ntdsutil to remove the application directory partition.
If possible, use the application's tool for managing its application directory partitions. The application may keep other data in addition to Active Directory–managed data for the application directory partitions. If you use Ntdsutil to manage the application directory partition, the two sets of data might cause a conflict.