I have an external HD (western digital) that uses USB 2.0 to connect. I plugged this device to my microsystem MCM765, but it isn't read and shows a message that says NO DEV. Sometimes, it shows a message that says UNPLUGGED. The information on my HD is on a folder with a deep of 2 or 3 subfolders (which is not the limit of the MCM765). PLS, I want to know why I can't use my external HD and Is there a way that I can use it? Thanks