A. If the demotion failed when you removed AD from a Windows 2000 domain controller (DC) to convert the DC to a member server, try the following approach:

  1. Use regedt32 to navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\ProductOptions.
  2. Change the ProductType's data value from LanmanNT to ServerNT. (Use the exact case.)
  3. Shut down and restart the server.
  4. Delete the NTDS folder.