Tanks for your suggestion for MS MapPoint and MS Streets & Trips.
1.BC-307 COM Port conflicts with Notebook:
Tested on both maps, no much difference can be seen. In Notebook, COM Port of BC-307 can be set to anyone (<20) which is not used by any OS program. MapPoint can automatically find GPS port. However, GPSInfo and MapPoint can not run at same time. If they are, port error will be reported. In addition, external atena is not essential.
2. GPS Port conflict with PPC Toshiba e740 and satellite fix
e740 can only figure out COM 1 for BC-370 GPS. External antena is a must to get satellite fix. Before running PPC MS streets, go to running programs and stop any programs using COM 1 (including GPSInfo). If not, port error will be reported. If setting is right, it usually gets a fix <2 min)