try this tool - when adding any new BT hw and pairing it it asks for you and creates a new com port
http://www.bonver.hu/www.igo.hu/download/bthtools.zip
works fine for me after install you need restart and upair all BT connections a build up newly - it will than ask for com ports - this tool resolves also GPS problems - although BT finds them - it does not assign them a com port to communicate or only outbound in WM5