Being

A slight aside: Like politicians and most corporates, Microsoft is driven by marketing. They love catch phrases like 'plug and play'. What they actually mean is that each device will be covered by a driver that will make it work on their operating systems. What they don't say is that their operating system is actually more basic and less clever than the slogan that their marketing people devised. Don't be fooled by words!

Having recently had the same 'device not recognized' message after moving my XP machine, I have read this thread entirely and have solved my problem by simply uninstalling all of my USB devices in Device Manager, shutting down and unplugging for half an hour then re-booting as normal with all devices in place. Win XP Home not only recognized all previously unrecognized devices but also found a driver online to make my aerial dongle work and told me how to make my Lacie external hard drive operate faster too! I have rebooted since and all is still good. I don't know if it will last or work for everyone. I seldom have a good word for Microsoft but this time they seem to have come up trumps. I think the key with most MS problems is to think as simply as possible. No need to format or fiddle with the bios or registry, just disassemble and let MS try to put it back together! Hope that helps.