Hi again! My Garmin 3790 now is dead. I desided to downgrade the software to 4.9 and something goes wrong and it can't reboot now. The pc view it, I upgrade it to the last software, but it can't boot. When i power on it shows only Garmin and switch off after 5 seconds. Can I delete all the files from it and after that to copy the files from another 3790?