@ utu

Did you read the section "USB settings" of Chapter 3 in the Virtual Box manual (available online at http://www.virtualbox.org/manual/ch03.html ). The manual says that you first have to create a filter for the USB device after installing the extension pack. "On a Windows host, you will need to unplug and reconnect a USB device to use it after creating a filter for it."

I think that the developers should invent a simpler procedure to use USB device.