Domain Controller could not be Contacted

Dear Guys,
If you have knowledge in networking only then reply here.
I have some problem in Domain Controller Configuration.
Server: Windows Server 2003.
Client: Windows XP SP2
When both are in same local network, client connects to DC,
But when I put the server in Live(static IP and put a real domain name) IP and try to connect from a client on remote location. Client says Domain Controller could not be contacted.
Any help will be appeciated.
Guys pls help me.
Thanks,
.
Answer #1
-:BUMP:-
Help me GUYS
Answer #2
ok describe in detail what do you wanna do, and i will be glad to help you . i did not get anything from “i put the server in live till the end.” so please rephrase.
Answer #3
the domain controller is working fine when runs under local LAN, but as soon as i have connected my DC to the internet and make it available for our clients who are very far from us, client machines didnt comes under domain.
Answer #4
are you able to ping the server with ip and name when you assign this a public ip(make it Live) from the client side(on wan)
have you proper add the dns server in client side.