Discovery Can't Find My Device

I’ve got a My World II 1TB (Blue Rings) connected to my o2 wireless II and I’m running Vista.

The blue rings are continuously lit, implying the device is ready to use, however I WD Discovery can’t find my device. If I go on to Network on Windows, the device shows up as a network computer named ‘Server’ and I can put things on to it, but I can’t access it in iTunes, which was the main reason for buying the device.

Has anyone had this problem or has a possible solution?

Thanks, Phil