This caused some serious havoc on a client’s network for half a day. I setup RAS as normal, and it worked great for about 5 days. All of a sudden, clients couldn’t access the mail server.

I check DNS and found an extra record of the mail server in there. I checked the NIC to make sure there were no extra IP’s bound to it. At first, I thought someone else might have named their machine the same asa the server..and thought..no way.

I went into RAS and saw a DHCP address for the mail server! I figured it had to be DNS. Sure enough, the “interface” tab in the DNS properties was accepting all IP’s. Here’s the fix:

1. Start DNS Manager.
2. Right-click the computer name, and then click Properties.
3. Click the Interfaces tab, and then click Only the following IP addresses.
4. Remove any Routing and Remote Access IP addresses that are listed.

Hope this helps!