We have about four VLANS all configured as part of the watchguard firewall. Windstream is our external DNS server and our Internal DNS servers are Windows 2003 servers. The issue is showing up only with VISTA clients. Windows XP clients work fine. What we are seeing is that we can ping external domains like msn.com, google.com, and we can do nslookup on these external domains. We can ping our internal servers including our DNS servers but we cannot do nslookup on any server that is internal. Our main campus website is hosted externally, but we have two websites that are hosted internally and we can connect to our external website, but when we try and connect to our internal websites it gets page not found. The only workaround that I have found works consistantly is to manually configure the host file on the vista machine for the two internal websites . The Vista clients are SP1. The Vista clients are DHCP clients as well as the Win XP clients. Both types of clients use the same DNS server entries in the TCP/IP config provided by DHCP. I just don't get why XP works and Vista doesn't . Has anyone found a real solution beside using a host file for vista clients that have NDS problems?

Bassically once I added a Windows Server 2008 R2 server as a DNS server the Windows Vista Name resolution problems were solved.