Joining a Win2K System to an Existing NT Domain

I use a Windows NT 4.0 server as the PDC in a small network (no BDC exists). I recently bought a new Windows 2000 Server Service Pack 3 (SP3) system to replace the NT 4.0 server. I planned to set up the new system in the existing NT domain, promote the Win2K server to a domain controller (DC), let the security database replicate, then remove the NT 4.0 server from the domain. But I can't promote the Win2K server in the existing domain. Every time I run dcpromo.exe, I get the following error: Naming information cannot be located because: The specified domain either does not exist or could not be contacted. When I try to connect to the domain, I get this error: The domain is not an Active Directory domain or an Active Directory domain controller for the domain could not be contacted. Can you please help me solve this problem?

What you're attempting isn't possible. Only NT 4.0 servers can act as DCs in an NT 4.0 domain; Win2K systems can act as DCs only in a Win2K Active Directory (AD) domain. Your best bet is either to create a new Win2K AD infrastructure and use the Active Directory Migration Tool (ADMT) or a similar tool to migrate your NT 4.0 SAM accounts or to add a new NT 4.0 server as a BDC in the NT domain, promote the system to the PDC (making the original NT PDC a BDC), then upgrade your new PDC to Win2K. The latter scenario will create a mixed-mode Win2K AD domain environment, which lets NT servers function as BDCs. If the resulting AD environment doesn't function to your satisfaction, you can always go back to your original network configuration by repromoting the NT BDC to the PDC, using Dcpromo to remove AD from the Win2K server, and restoring the NT domain environment. If everything goes as planned and you're happy with the new Win2K AD environment, you can upgrade the old server to Win2K and continue using it as a BDC or demote it to a member server.

Having said that, if you're going to upgrade, I suggest that you strongly consider upgrading to Windows Server 2003 rather than Win2K. The newer OS is faster, more secure, and has better role-based management, as well as other features that you'll probably find useful. For some great information about Windows 2003 and its new features, visit http://www.wininformant.com and http://www.microsoft.com/windowsserver2003/default.mspx.