This is a common error that is returned when the communications port is unavailable.
Either the port is busy, already in use, or it is not installed.

It has nothing to do with XP, check your device manager and ensure that your com ports in question are installed. Then make sure no other devices or softwares are using that port. Modems or fax software etc.. use the com port.

See FAQ ID: 7943 for information on determing which ports are available

Also, if you have already opened the port you may get this error. Typically, I always close the port, before I attempt to open it. Just to be safe