Pretty sure you need to go into control panel and find devices folder(may be called something different in XP and Vista)then look for yellow marks/sign that indicates a conflict and work it out from there.One thing more. With usb, the com ports are more theoretical than regular serial ports. You don't necessarily equate a com port number with any physical connection as you can add devices to many connectors physicaly, even add physical connections with a hub or some devices can be daisy chained together makine a lot of devices connect to one physical connection point on your computer but they all need com port numbers. Sorry if I confuse you but I'm not the best at explaining things. I don't believe your problem is a great or insurmountable problem. Good luck.
Terry
Terry
