I've seen this problem already posted, but with no solution.
I have a brand-new Dell XPS 13. The right side USB drive functions, in that the drive shows up on Windows Explorer, and I can copy files to and from it. But autoplay on the right side does not function, so nothing happens when the drive is inserted. This only happens on thumb drives; hard drives seem to work. It's frustrating, because when I insert the thumb drive, I would like a window to pop up...but it doesn't work.