The specs of the Japan ext. HD must be ready for the OS of your laptop and be a match of the port you're using. Unless, there is some buried h/w firmware of regional issue, then it should work. You do need to format and/or prepare the ext. HD to be used as it maybe not ready for English use.

You did bring these issues up when you brought it or similar? Plus, how is it powered? Wink

tada -----Willy Happy