When you try to join a Windows Vista-based client computer to a top level domain (TLD) that has a purely numeric suffix, the Windows Vista-based client computer cannot join the domain. Additionally, you receive the following error message:

Computer Name/Domain Changes
An Active Directory Domain Controller for the domain could not be contacted. Ensure that the domain name is typed correctly. If the name is correct, click Details for troubleshooting information.

Note: An example of a purely numeric suffix is “contoso.2003.”

When you click Details, you receive the following error message:

An error occurred when DNS was queried for the service location (SRV) resource record used to locate an Active Directory Domain Controller of the domain domain name.

The error was: “The filename, directory name, or volume label syntax is incorrect.”

(error code 0×0000007B ERROR_INVALID_NAME)

The query was for the SRV record for _ldap._tcp.dc._msdcs.domain name.com

If you try to join the domain by using the NetBIOS name of the domain, you are prompted for domain credentials. In this case, the client computer still cannot join the domain. Additionally, you receive the following error message:

The following error occurred attempting to join the domain NetBIOS name of the domain Logon failure: unknown username or bad password.