Remove active directory from this computer without updating forest metadata
Make sure Exchange 2003 is not using this DC for OAB or RUS. If Exchange 2007 or 2010, Exchange will automatically discover the change. If not sure how or options to choose, read the following links.
Disable the Global Catalog service from the domain controller.
Check ADUC, Domain Controllers OU to make sure it’s gone. Actually this is the preferred setting, where all DCs should point to themselves as the first entry, and another DC in its own Site as the second.
You should now find the old DC computer object in the Computers Container. Change DNS settings to it’s own IP address (to itself). If no other DCs are in its own Site, choose one across the WAN with the fasted link.
Restart the DC OFF the network On this DC, run “DCPROMO /FORCEREMOVAL”Run the Metadata Cleanup procedure to remove it’s reference on a current DCIf you want to reintroduce the old DC, you can simply promote the old DC back to a DC How to remove data in Active Directory after an unsuccessful Domain Controller Promotion Clean up server metadata: Active Directory, Mar 2, 2005 to run Metadata Cleanup Procedure: Script to Remove Active Directory Domain Controller Metadata Microsoft: The Scripting Guys, Published on 8/10/2009 Center/en-us/d31f091f-2642-4ede-9f97-0e1cc4d577f3 Delete Failed DCs from Active Directory This link put together by Dan Petri, includes screen shots.
Change the DNS addresses on the DC to point to an existing DC/DNS server in the same AD Site.Ace Fekay, MCT, MVP, MCITP EA, Exchange 2010 Enterprise Administrator, MCTS Windows 2008, Exchange 2010 & Exchange 2007, MCSE 2003/2000, MCSA Messaging 2003Microsoft Certified Trainer Microsoft MVP: Directory Services Active Directory, Exchange and Windows Infrastructure Engineer Original Publication: 10/9/2010Updated 12/27/2011 – added time service configuration info.