I have an old hard drive which I'm trying to use on my Windows 7 system. It did work and does still work on an XP system but now for reasons which I can't understand no longer works on Windows 7. The disc appears in Device Manager alongside my installed 'C' drive but it doesn't appear on Computer Manager display. Can anyone shed any light on why this might be? I haven't changed any hardware recently and software changes are mostly Windows Updates.