Adprep.exe is a command-line tool used to prepare a Windows 2000 forest or a Windows 2000 domain for the installation of Windows 2003 domain controllers. In earlier versions of Windows Server 2003, running adprep /domainprep added an inheritable access control entry (ACE) to all Group Policy objects (GPOs) in the SYSVOL folder. This ACE gives enterprise domain controllers read access to the GPOs to support Resultant Set of Policy (RSoP) functionality for site based policy. The File Replication Service (FRS) detects the addition of the ACE and initiates an FRS synchronization of all GPOs in the SYSVOL folder.

In Windows Server 2003 SP1, the ACE is not added to the GPOs in the SYSVOL folder while adprep /domainprep is running. A new switch (/gpprep) for adprep adds the inheritable ACE to the GPO folders in the SYSVOL directory. This allows administrators to update the ACE of the GPO objects at their convenience.

Letting the administrators determine when to update the ACE of the GPOs makes it possible for this operation to be planned and scheduled as part of the deployment. Otherwise, if an organization has a large number of files contained in the GPOs or slow links to replication servers, the FRS synchronization triggered by the /domainprep operation can adversely affect the deployment schedule for Windows Server 2003.

Tip

The deployment of a Windows Server 2003 domain controller can occur after you run adprep /forestprep and adprep /domainprep. RSoP functionality will be operational only after you run adprep /gpprep.