DNS or WINS are to resolve the host names. First of all, you ensure that you can access the resources on the remote site by using the IP addresses, not host names. For example, you can try to establish Remote Desktop Connection with a remote host by typing the IP address of that host. If you can establish, then try same thing by using the hostname of the same PC. If you fail to establish, then it is a DNS related problem. If you fail on both the occasion, then you have to check some thing else.