I installed Windows 8 on my desktop and then attempted to install the Arduino Due driver.
Windows 8 refuses to accept the Arduino USB driver because it is "unsigned". The message returned is: "The third party INF does not contain digital signature information".
Previous renditions of Windows allowed you to override the "unsigned" warning and continue, Windows 8 will not allow installation of a driver without the proper digital signature.
Looks like a show-stopper for Windows 8 users.
Cheers,
Jim Lynch