Unable to register DNS when the systems are directly connected to the internet if ISA 2004 client is installed

Setup: Windows Domain
Server: 2003 RC2 Std (With AD, DNS, ISA 2004)
Clients: Win XP (desktop and Laptop)
Internal IP range: 10.82.4.x

Internet: Leased line, connected directly to Win Server on 2nd NIC., Shared thru ISA Server 2004 with FWC installed on all clients except a few laptops. Those few laptops have the gateway as this server.
Those laptops with the FWC installed, when taken outside office premises and connected onto a different ISP for internet, gets connected, but the DNS still points to the office Win server (private IP). Hence, the IPs do not get resolved and cannot browse except if you know the IP addresses. The laptops ping to all public IP. There is no change even when the FWC is uninstalled. The ipconfig/all shows the public DNS servers of the dialup connection but the nslookup points to the office DNS (10.82.4.4). Corruption is ruled out as all the laptops with FWC are in the same situation.
Those laptops where the FWC was never installed, work fine on the above scenario.
BigflicksAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

robrandonCommented:
Is the TCP/IP Properties of the network connection setup to Obtain DNS server addresses automatically?  This is the setting beneath the Obtain IP addresses automatically.  It is possible to get a DHCP IP Address, but not the DHCP DNS servers that way.
0
BigflicksAuthor Commented:
Yes the setup is as u said
0
robrandonCommented:
Have you looked through this MS article at all?  It explains the correct way to setup the autodetect settings for ISA 2004 and the FWC.

http://technet.microsoft.com/en-us/library/cc713344.aspx

0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Microsoft Forefront ISA Server

From novice to tech pro — start learning today.