I have two machines set up behind a router, and both are windows 7. I set up port forwarding on the router into the two machines and they both have consecutive assigned ip addresses. One computer I can connect to remotely just fine from outside the network, but the other one I can't.
I've been troubleshooting the problem by remoting into the machine that I can get to and then opening an RDP from that machine to the other one and it opens fine. So you can RDP from one machine within the network to the other but not from outside to that machine.
It's obviously listening on 3389, and I confirmed that with netstat. The outside port (I'm forwarding from external 3390 to internal 3389) is open and the router works fine. I changed the port forward so it was pointing to the other machine and it worked fine that way so presumably the router is forwarding fine.
I don't understand why I can make a 3389 connection to that machine from inside the network but not from the router.