If you are using desktop computer, make sure ND2730 is connected to USB port located on the rear side of desktop computer. Front side USB port of desktop computer does not offer good connection and can make problem using high speed device like ND2730. It is only for slower device like mouse or keyboard.
Or, please check here to know how you can find your USB drive at Windows 10.
https://www.thewindowsclub.com/usb-3-0-external-hard-drive-not-recognized