When you attempt to add a host to a Windows 2000 domain, you receive:

Network Identification
The following error occurred validating the name <DomainName>
The specified domain either does not exist or could not be contacted.

This can occur is the DNS zone file uses an alias (CNAME) record as the target host of the Service Locator (SRV) records instead of a host or A record:

<b>   _ldap._tcp.dc._msdcs    600 SRV    0 100 389 pdc.<Domain>
   pdc                     600 CNAME  dc1.<Domain>
   dc1                     600 A      192.168.0.1</b>
where pdc.<Domain> is an alias for dc1.

To fix the problem, change the target host of every SRV record in the DNS zone for Active Directory to point to a host or A record.

NOTE: When you join a Windows 2000 domain, the client looks for the SRV record of _ldap._tcp.dc._msdcs.Domain. If this points to an alias, the client ceases its attempt to join.