I cannot add computers to my domain

I am getting an error when trying to add a client to my domain. I set up a domain controller and when I try to add a client PC to it I am getting an error "A domain controller could not be contacted...." I am running windows 7 64 as the host. and using MS virtual server. I got 2 server installed and 1 client. Just can get the client added. Any ideas? Does anyone have any links to tutorials for setting up labs?
Thanks
Thanks
Comments
1. Is DNS properly setup? Is the client pointing to the dns server either through dhcp or static?
2. On Virtual Server, do you have the DC's and client on the same network?
MCTS: Windows WS08 Active Directory, Configuration
also check out the server that is the has the infrastructure FSMO role.