[avgas]

I am using RDP to remotely access my vista PC, It works perfectly when I use my home Wifi connection, the same on which the PC is connected to, but when I try to access the computer from any other place, I get connection errors.
I guess it works on a local level, when I use the wi-fi from the modem the PC is connected to, i get in just fine. I have a port set up and all, am I using the wrong IP settings? Thanks