I usually hear the opposite happening JR. I usually hear that people are able to install the OS with XP but can't with Vista. As Jeff said, there is probably something that is causing the updates to fail. I would try deleting and reinstalling Desktop Manager and the whichever OS you want to update to on your computer. i would also disable any internet connections and your firewall temporary to see if that is the cause. You can also try deleting the vendor.xml file from C:/Program Files/Common Files/Research In Motion/AppLoader/.
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