Ok, this is a somewhat complicated problem.
Let me start with the network set up:
1. IIS server
3. Internally hosted DNS server
4. External ISP DNS server
The problem I am having is that people are automatically pulling DNS servers to use. They are grabbing the external ISP DNS to resolve domain names. We have a domain name within the firewall.
Sometimes, users pull the external IP address (65.xxx.xxx.xxx) and are not able to resolve to the website. Sometimes the users pull the internal IP address (10.1.1.23). The domain name should be linked with the internal IP address when within the firewall.
I think the only solution to this is to force users within the network to pull the internal DNS server and block the external DNS server. However, with lap tops this is an issue because often users are sometimes within the network, sometimes without. With desktops, we force the DNS look up to the internal DNS and we have no problem, however with laptops I am at a loss how to solve. Any ideas?