When you plug it into your computer, does it pick up the usb device has been connected to the computer. Did a CD or anything come with the Dongle? You may need to install the driver for it onto your computer. If you have an windows XP computer, it may not automatically install the driver for it.
Not to be rude - but are both bluetooth devices definitely turned on - in both your dongle and PC?
You could try to see if you can connect another mobile phone to it.
