Hi. Huawei E220 supports Windows XP out of the box, but requires firmware and software updates in order to use it with Vista, which are detailed and simple to do, as detailed here - http://www.mobileconnected.co.uk/usb-modem-huawei-e220-on-vista-take-2/ The Globesurfer Icon 7.2 and 7.2s support Vista directly according to our contact ...