Active Directory Schema (AD Schema)

The Microsoft Active Directory schema contains formal definitions of every object class that can be created in an Active Directory forest. The schema also contains formal definitions of every attribute that can exist in an Active Directory object. This section provides the reference for each schema object and provides a brief explanation of the attributes, classes, and other objects that make up the Active Directory schema.


The following documentation contains the programming reference for Active Directory schema. If you are an end-user attempting to debug a printer error, try searching on the Microsoft community site. If you are a developer looking for a general overview of Active Directory schema, see the Active Directory Schema overview topics. If you are looking for programming guidelines for updating or modifying the schema, For more information about extending and customizing the schema, see Extending the Schema, as well as many of the topics in the Active Directory Domain Services and Active Directory Lightweight Directory Services programming guides.

In each of the reference topics, there is a section for each operating system that the topic applies to. The following operating systems are currently supported.

Platform Name in topic
Microsoft Windows Server 2003
Windows Server 2003
Microsoft Active Directory Application Mode (ADAM)
Microsoft Windows Server 2003 R2
Windows Server 2003 R2
Microsoft Windows Server 2008
Microsoft Windows Server 2008
Microsoft Windows Server 2008 R2
Microsoft Windows Server 2008 R2
Microsoft Windows Server 2012
Microsoft Windows Server 2012

If an operating system is not listed in the topic, the topic is not supported on that operating system. For example, if a topic only lists Windows Server 2003 and ADAM, then the topic does not apply to Windows Server 2003 R2.

The following sections contain detailed information about the Active Directory schema elements.