Navigation wont work??

Hi Guys, I recently Bought a high speed my gig. for my 3.7 the system works fine exept for the navigation, Lets say I put in an adress it just keeps looking for hours, the bars at the bottom just keep going back and forth. When I tried to check the map, It tells me drive to a digitalised road?.... and when I open the GPS info It shows No Satelites>? PLS anyone know how to fix this its been DRIVING me crazy *) thanks!!!