Report "When switched on will only display NAVMAN logo and the "N401". The N40i text has a highlighted N and dimmed 40i. The orange charge light is on, but does not appear to charge the unit. None of the buttons work. My PC detects the unit and I can apparently upgrade the maps, but as soon as I disconnect from the computer, the nit will not boot up. Any ideas? (It was like this after been returned from a "friend")"