Mike Your comment about Windows Vista is right on target. NavigatorV(R) uses a Microsoft developed communication protocol (WSE) for EZ Update that is supported on Windows XP and early Vista test kits. However, Microsoft made a number of late changes to Vista including updating the communication protocol in the initial release version. For this reason, EZ Update did not work on the initial Visa release however Microsoft released a Vista upgrade that fixes compatability issues with the communication protocol in Vista. ATP NavigatorV is fully funtional with WSE 2.0 SP3 installed on Vista.