Firstly I had to smile at the error message which was surely written by someone with an IBM background in mainframe technologies. DASD is the common term for any form of storage drive technology going back maybe to the early 1990's or before that (even I'm not the old) - my first employment with IBM was in network operations - and some of that involved the SNA networks. The other point I was going to suggest is that this is a USB 3.1 drive of 256GB capacity unless Mr Google has let me down? Do the specs not heartily recommend USB2,0 drives no larger than 32GB? I thought that the larger specifications required less reliable storage controllers or some such? Just a thought though