I added a new Windows 7 Pro machine to our LAN (Windows Server 2008 R2) and am having the usual problems of trying to connect to it remotely, from outside our LAN, with Remote Desktop.
I have other machines with Windows 7 Pro and connect to them and I don't remember all the things I did on them to make it work. Of course I enabled remote connections in the properties, and I added a specific rule in for incoming traffic in the firewall on the port I'm targeting.
There is a NAT configured on the router to forward to the local machine:
Protocol Start Port End Port Local IP Address
PC1 ALL 3397 3397 192.168.16.52
PC2 ALL 3396 3396 192.168.16.29
For example, PC1 works, from inside the LAN if I connect to 192.168.16.52:3397, and also if I connnect from the outside on our public static IP with : 217.xxx.xxx.xxx:3397 - no problem.
Here is perhaps a clue to the problem, PC2 doesn't work from the outside with 217.xxx.xxx.xxx:3396, BUT - it does work from the inside with simply : 192.168.16.29 and also with the hostname - without specifying the port. I have the standard RDP port, 3389, pointing to the server, and that works normally, from both the inside and outside.
So why can I connect to it on the inside without the port - if add the port it doesn't work - which is probably the same reason it doesn't work from the outside. Apart from adding a specific firewall rule for port 3396 to allow incoming traffic on that machine and enabling complete RDP access, I don't see what else I can do. I must have done something on the other machines, but I don't remember what.
That way, when we RDP to wan IP with port 3396, it gets forwarded to pc2 default RDP port 3389.