After receiving email with appropriate code to upgrade maps I deleted the maps from my500xt intending to install year 1 of 3 free map upgrades - now unable to get the my500xt to operate. Did repair on PC navman program using my original disk but that did not install original map (Australia). Connected to computer navman screen shows picture of navman connected to PC with signals bouncing from one to the other.

GPS - Navman - iCN 530 GPS Receiver