We have SBS2003 with a single network card.
We have just changed ISPs and routers
We are now using a Draytek router with fixed IP and port forwarding ports 25, 80,443, 1723, 3389 and 4125 to the network adapter on the server.
The old router (also a Draytek) was IP adddress 192.168.40.254 and all was working fine.
I set up the new router on the network as address 192.168.40.253
I reran the Internet Connection Wizard and changed the default gateway to the new router
All works fine apart from OWA and RWW - VPN have reestablished and mail comes in ok.
Both OWA and RWW work normally on the LAN.
Accessing externally I can confirm that port 25 and port 80 are forwarding ok
however when i try the /remote or /exchange options I get a "Page can not be displayed" message "The page you are looking for is currently unavailable".
It doesn't switch to https and I don't get the certifictae downloaded (I have recreated a new certificate)