I have the same issue. My 2TB 3.0 USB external hard drive has stopped functioning (Made from Buffalo Inc). Once I connect it to my desktop it makes a sound (I think it is a clicking) for a few seconds and then the noise stops. The light is still on but my computer does not recognize it. I can see it in my "Printer and Device," but that is about it. I can not get access to it. I have connected to my Mac with no success. I also changed the USB and no success. I am just wondering what is exactly my problem. Is there a chance I can still get access to my files and how?
By the way, if I had this external hard drive on when I turn my Windows10 desktop, it won't let my desktop completely turn on, it gets stuck. However, once I turn the external hard drive off, my desktop will proceed smoothly.