Still does not solve my problem, but keep trying to find a solution before sending to Garmin technical support, which charges too much for service. Apparently the problem seems to be MBR partition table corrupted, but I can not access the drive at all, despite appearing "Garmin USB GPS" in Device Manager of the W7. My big problem now is how to access the drive. Does anyone have any ideas or even the suggestion of a tool that can access it? WebUpdater identifies the unit, including the GPS ID number, but when try to do the upgrade reports error, "corrupt file" and aborts the process.
Only the fw 5.40 cure with strings 30 00 3A 00 2F to 00 00 3A 00 2F; 31 00 3A 00 2F to 00 00 3A 00 2F; 30 3A 2F to 00 3A 2F and 31 3A 2F to 00 3A 2F to prevented the looping boot and was the only that displays the screen "System Software Missing". With other Cures, Garmin logo appears and is boot looping (constantly restarting).
I appreciate any, any, help, tks... (nuvi 1390T HWID 972 - the last fw used was nuvi 1360 japan fw 3.00 + boot.ini USA, but it worked perfectly for over one month).