Reply by frankz00 on December 30, 2008 This software is not for actual GPSs. It's for USB devices that read NMEA satellite data to turn your laptop into a GPS. This means it tests the device you need to run mapping software on your laptop. These devices typically come with a USB to COM translator so that the mapping software sees a COM port to read NMEA data. That is the part that this software tests. In other words, the Garmin eTrex doesn't feed NMEA into the laptop and therefore it would not be detected.