Yeah, try the adapter. I have had a problem with a keyboard in Vista before. It was caused by a MB utility (ASUS Maximus Formula X38) that was a bad application from the MB maker ASUS. Eventually ASUS put ourt a fix and the 'bad' keyboard issue was solved when running the utility. So, maybe something in your system is conflicting when you plug it in. I mean, your friend's same MB works in VISTA, but he does not have the same system, MB, CPU, hardware and software installed for that matter. yeah, try the adapter and running it as a PS2 setup.