After I updated my PC to Windows 8.1, when I plug in either of my two 3TB USB3 My Book Essential drives, it gives an error “USB Device Not Recognized” and, of course, Windows doesn’t see them. They worked fine on Windows 8. My other external drives (My Book 1TB USB2 drives) work fine. Other USB devices work fine on the same USB3 ports. Any ideas?
Looking at some Windows forums it appears that Windows 8.1 has plenty of bugs in the hardware dept.