USB/not loading

HI. I'm totally new. That's why I decided to start with xdj-700 since It's very small and handy to carry. But at this moment just bought it and want to start. After instalation when connected my usb stick, he didn't read it at all. No sign. It says : no usb found. This is the  same usb stick that I've connected it a few times with a pioneer 3000 so I don't know what happens. Any tips? thanks