Single-label domain names can be used (as you've already discovered), but are not advised because of the extra management burden and
rather obscure problems they create. If you add Exchange Server to the mix it is almost an impossible configuration.
This will get you started on the details.
http://support.microsoft.com/?id=300684
A Google groups search on "single label domain name" should turn up quite a bit of useful material also, as issues relating to this
make frequent appearances here.
In your case a domain rename if at all possible is to be recommended before deploying another DC or making schema changes, but there
is no great answer to doing that in your case.
If you will be at a Windows 2000 functional level for the foreseeable future, have to keep the domain name you have and live with
it, or tear down the domain and rebuild it with a new name (the ADMT2 tool can help).
Native Win2K3 mode does support a domain rename operation, but once on that you can't move back to Win2000 DCs, so a
'back-and-forth' migration with the two servers to rename the domain will not work. You need to upgrade your Win2K Server to
Win2K3 - and despite the added cost that could be the wisest approach.
An adprep on a single-label domain name has been known to be a wee bit touchy. If you (1) follow the recommendations in 300684, (2)
make sure your updates and SPs are current, (3) make sure that all the domain config. tests check out perfectly, and (4) get a solid
AD backup (and know your DS restore password!), then you can try it. Nobody here is likely to guarantee you anything though.
Steve Duff, MCSE, MVP
Ergodic Systems, Inc.
Thanx. We are going to build a new Win2k3 server/domain, migrate data from win2k server, then rebuild the win2k server to join the win2k3. Clean and prestine works for me!
