Hi,
this problem with HDD and Bravias continue to catch people out, this lack of information on this will always cause problems for many of us and still Sony sit on the side and expect the majority of us to work it out for them!,
As i see it you can only register the HDD to the tv when its plugged in via usb so its only logical that to un register it, it will need connecting to the tv first, there should be a prompt to un register it then.
