Remote Desktop to Windows SBS 2003

I have set up a SBS and enabled remote access through the wizard. I can access the remote desktop from computers on the LAN but when I try to use remote desktop connection on any outside computers to access the server it will not allow me. What am I missing?

Obviously I got the server with SBS 2003 preinstalled so I did not configure it by scratch.

Also, actual domain name is XYZ.local and not XYZ.com.

I hope this is enough info to go on. As you can tell, I’m new at this and doing it as a favor for a friend. Thanks in advance.