When I try to promote a Windows Server 2003 domain controller (DC) into a Windows 2000 forest, the action fails with a schema error. How can I resolve this problem?

A. Windows 2003 contains an updated schema that isn't compatible with the basic schema present in Win2K-based domains and forests. To resolve the problem, you must run the Adprep command from the Windows 2003 installation CD-ROM to update the Win2K-based domain and forest schemas. Before you perform the following actions, ensure that you've installed Win2K Service Pack 2 (SP2) or later on all Win2K DCs:

1. Identify the Schema master for the forest and the Infrastructure master for the domain. For information about how to do this, see other FAQs in the Active Directory (AD) section on the "FAQs for Windows" Web site, including the FAQ titled "How can I find the current FSMO role holders in a domain/forest?".
2. Disconnect the Schema master from the network.
3. From the Schema master, insert the Windows 2003 installation CD-ROM, open a command session, then type

   <cd-rom drive>:
   cd \i386
   adprep /forestprep 

4. Ensure that no errors were displayed or written to the event log and that domain functions such as Dcdiag still work. If everything is OK, reconnect the Schema master to the network.
5. If the Infrastructure master is on a different machine than the Schema master, wait 15 minutes for the forest change to take effect (or up to half a day if the machines are in different sites).
6. From the Infrastructure master, insert the Windows 2003 installation CD-ROM, open a command session, then type

   <cd-rom drive>:
   cd \i386
   adprep /domainprep 

The changes will then replicate across the domain (this process can take just 15 minutes if the Schema master and Infrastructure master are in the same site or as long as half a day if the machines are located in different sites). After the changes replicate, you'll be able to promote the Windows 2003 server to the desired domain as a DC.