I've got a bit of a strange one, its either related to my router or Server essentials 2012, but i can't find anything wrong on the router yet, so I thought i'd try here. I recently swapped out a basic linksys router for a Cisco RV042G, as part of a future plan to link to sites together. I copied over all firewall and static IP assignments, and bingo! everything is peachy. Except, they can't resolve their own website. Of course, i assume this has to do with the router, since it wasn't an issue before, but i can't see anything wrong. So, i'm assuming i might have done something wrong on the DNS module of SE2012, that was somehow a non-issue until i switched to a "pro-sumer" router. They can visit any website, but their own.
server has its own IP, as well as 2 ISP and 1 Google DNS entered into the NIC settings, but just 2 ISP and 1 google DNS entered as a forwarders.
computers connected to the network, use the Server's IP, and one ISP DNS address.
this is driving me crazy and i think i don't quite know enough, and instead have just made myself dangerous, instead of useful.