I too had trouble updating my hand controller to the latest firmware version. I was connecting it to my computer using a serial to usb cable, but it would not update. After reading advice from other users on this site, I decided that it was probably the usb to serial cable. Fortunately my partners computer had a serial port. After connecting my hand set to the serial port the update went ahead with no problems and is now running fine. I would advise other people having updating problems not to use the usb to serial cable and try to use a computer with a serial port.