Just installed two workstations using W7 Professional. I cannon join the wired network on Windows 2003 R2 server but can access internet and see other computers in network as well as map drives on other computers. Error message refers to not being able to find DNS server.
Helo and welcome to the forums.
That is a common problem. And is a result of whatever is handing out DHCP addresses for your network not being configured (scope) to hand out the proper DNS servers (probably your domain controller) for your Domain. Usually this would be configured with having a machine (possibly also the Domain Controller) as the DHCP server for your domain and configuring the scope options to hand out the DNS address with the other DHCP information.
Alternately you can manually assign static values from within the properties of the client machines network adapter, under Internet Protocol Version 4 properties, to point to your Domain DNS server as the primary (preferred) DNS server and perhaps using either your router or ISP's DNS servers as secondary (alternate) DNS servers.
Good Luck and keep us posted