At first, my computer did not detect the B153 as a mass storage device. It turns out you have to slide the HOLD switch on the back of the device to the hold position. This is stated in the instruction manual, but I apparently missed that page the first time I read it. Once I slid the HOLD switch, the PC immediately detected the B153 and the display on the B153 clearly showed "CONNECT". While files are being transferred to or deleted from the device, the display changes to "DON'T DISCONNECT" much like the iPod.



Link: Pocket Now