I have been battling Vista, in trying to get our new systems attached to our Windows 2K server for some time now, and I thought I might save someone some of the hours and frustration that I went through, by posting some hints here. Don't know if this will help anyone else who ends up here, but here's what I discovered.
All of a sudden our Vista machines started hanging at logon and acting downright glitchy all around. After a lot of web research and poking around on the server I discovered that in services.msc our DNS Server was set to manual, and had not started. After starting the service, just as suddenly the logons appear to be working fine.
On a somewhat related note, earlier on I was confronted with Vista not even seeing the domain. I could gain web access through the proxy server, but could not join the domain. Came to find out that in our server's advanced TCP/IP settings that the DNS server was listed by the loopback address 127.0.0.1 AND NOT the actual DNS server's address. Unfortunately for me I lost hours trying to figure this out. Every other OS worked fine - including XP - with this scenerio but Vista is obviously VERY particular with DNS settings.

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