You add a new network adapter to a Windows Server 2008 R2 server that’s running TMG, and the new NIC doesn’t show up in the Network Interfaces section of the RRAS console on the server? Interestingly, in this situation the NIC does show up in the Network Connections section of Control Panel’s Network and Internet app.
Luckily, the solution has been posted over on TechNet’s ISA blog, where you can find the simple steps required to fix the problem: