This morning I uploaded a book to my PRS-505, it did that ok. I then disconnected the reader and found the book on the reader, it said formatting a long the bottom of the screen. When it finished formatting i then went back to the main menu screen and now it wont do anything...I've had it plugged in to my AC power charger so I know the battery isnt flat, I've tried pressing the reset button on the back but nothing has worked......I've even tried plugging it in to my USB port in the hope it might jump start it. But nothing has worked......I dont know what to do........