Before you can start enabling functional levels, you have to go through the process of upgrading your existing infrastructure to Windows Server 2003. The first step before you can promote your first Windows Server 2003 domain controller is to prepare the forest with the ADPrep utility.
If you’ve installed Exchange 2000 into your Active
Directory forest, you are undoubtedly familiar with the Exchange
switches. These switches are run independently from the Exchange
server install to allow Active Directory administrators to take care
of the AD-related tasks necessary to support Exchange. The Exchange
/forestprep command extends the schema and adds
some objects in the Configuration Naming Context. The Exchange
/domainprep command adds objects within the Domain
Naming Context of the domain it is being run on and sets some ACLs.
The ADPrep command follows the same logic and performs similar tasks
to prepare for the upgrade to Windows Server 2003.
Microsoft recommends that you have at least Service Pack (SP) 2 installed on your domain controllers before running ADPrep. SP 2 fixed a critical internal AD bug, which can manifest itself when extending the schema. There were also some fixes to improve the replication delay that can be seen when indexing attributes. If you plan on supporting a mixed Windows 2000 and Windows Server 2003 environment for an extended period of time, Microsoft recommends that you have SP 3 on your Windows ...