I have recently been trying to get Garmin Mobile PC to work with GPS Gate. As everyone else I was having no luck until now, It can be done.
Garmin Mobile PC will not recognize the Virtual Com ports created by GPS Gate. I first determined if Garmin Mobile PC would recognize the NEMA data stream created by GPS Gate. I installed a multi port serial card in my PC and tied two of the ports together with a Null Modem cable. I then Added an output to GPSGate and selected COM Port option (NOT Virtual Com Port it is further down the list). In this setup GPS Gate acts like a NEMA GPS connected to the second COM port. Starting Garmin Mobile PC it would recognize the GPS on the second of the COM ports and it worked.
The next step was to replace the multiport serial card with a Null Modem emulator. You read more about these things here.
I used a open source (free) one located at;
Click on the com0com link then follow the download links and download com0com-126.96.36.199-i386-chk.zip
Install the program, the instruction make reference to configuring everything via a command line, however there is a GUI configuration utility installed in the program group. The only thing that may need changing is the COM port names.
Now set GPSGate to feed NEMA data to the higher number of the two ports at the default baud rate of 4800. The baud rates and using the higher of the two ports is what first worked for me I don't know that it is required for sure.
Run Garmin Mobile PC it should now find a GPS at the other Virtual Null modem port.
The data flow is something like this.
GPSGate->Virtual Null Modem Port 1 -> Virtual Null Modem Port 2 -> Garmin Mobile PC
The virtual COM ports created by com0com do not show up in device manager however they do show up in Garmin Mobile PC. You can see them by;
Settings -> System -> Remote GPS -> Disable
So Garmin Mobile PC will work with Virtual COM ports just not the ones created by GPSGate. I'm glad I don't have to figure out the causes of these problems.
I hope other people with this problem will also find this thread.