Manuel has a Lenovo A2109 Tablet and he'd like to hook up a portable hard drive to it. It isn't working because his portable hard drive isn't powered, and the tablet doesn't seem to be giving it enough power to work.
Manuel will need a bus powered cable that has a splitter with two USB ports, one to a computer and one to the tablet. The Lenovo tablet uses a function called USB On The Go which supports that. The chatroom says that another option is a powered USB hub. Plug the portable drive into that, and then plug in the tablet and he'll good to go.