Micco: Really sorry to hear about your continuing Tyros/PC USB connection problem. I'm able to run the Yamaha Voice Editor & File Utility with Windows XP Home with my Tyros fine. If you have the latest Yamaha USB midi software drivers correctly installed, I suspect your problem might be hardware related: possibly a faulty USB cable or faulty USB connection inside the Tyros or in the PC itself. I think you definitely need to contact Yamaha Technical support about this. Good luck and keep us posted. - Scott