I tried both the programming and native USB ports, in a Windows 7, Windows 8 and two Linux machines, but my new Arduino Due is not detected. The power led is on and the L blinks about once a second - which seems to be the factory sketch loaded.
I also tried to power it differently, with a 850mA/5V adapter, and a 2x to one USB Y cable with no luck.
I would have thought the ATMega16U2 was bad, but if that was the case why isn't the native port being detected either?
I'm a new user and really don't know what else to try.