Unable to Login to windows 2000 DC

I have managed to setup my Active Directory between my LAN and DMZ network across the firewall.

I have no problem doing NET USE commands and joining the domain. However, if i try to login from a machine on the DMZ network, I can only login with the domain adminisrator account. Normal user account will be unable to do so.

The error messages that I am receiving at the Windows 2000 logon screen is “The system can not log you on due to the following error: There are no more endpoints from the endpoint mapper. Please try again or consult your sys admin.”

Have anyone encounter this problem before and have managed to solved it? Appreciate if any gurus / firewall expert to guide me here.

Thanks in advance.