If you are running Windows 10, try using the new "USB GPS" setting in Menu > My position > GPS Settings. This option will allow you to use your USB GPS device without any other software.
If the "USB GPS" option doesn't work, you will need to run another software while using Maps Pro. This software is called GPSDirect. If you are in this case, this guide explains how to use and configure GPSDirect so that it can be used with Maps Pro, here with a "GlobalSat BU 353 S4".
Connecting the GPS
Connect the GPS to an available USB port. Windows will automatically install the device, so wait until the process is over.
Installing the GlobalSat Windows USB Driver
The GPS comes with a CD. Run it and click "Windows USB Driver", then follow the install wizard. This could be an optional step but might help with other software.
Head to this link: https://www.gpssensordrivers.com/ and download the executable that correspond to your Windows (32 or 64 bits).
Right-click the .exe file and select "Run as administrator".
Note: If you don't want to do that every time, right-click > Properties > Compatibility > Select "Always run this program as administrator".
The software will open and say "GPS Sensor not installed":
Then you will need to find the correct COM port in the NMEA Source list. Easiest way to find is just to try them one-by-one. If it is not the correct one, it will pop-up "Cannot open this COM port". Usually, the right port will be COM3. Make sure you change the Baud rate to the correct number, 4800 in our case. Otherwise, your coordinates will stay at 0.
When you will have found the right port, it will ask if you want to install the driver for this device, click Install. Wait for a few seconds and the Testing part will change to show your location information
If you are indoor, your tablet / computer won't be able to read any satellites. Once you get outdoor, the number will change. To have a nice geolocation, you need to have at least 3 satellites in view.
Maps Pro configuration
Open Maps Pro. Open the bottom menu > Help > Options. Make sure the first option is selected "Built-in GPS / Wifi location / GPSDirect". Right underneath, a message should say "GPS Signal status: Ready".
Open the menu > My position > Refresh my position.
Your position will be displayed on the map accordingly to what GPS Direct sends
When I go to Help > Options, it says "GPS Signal status: Disabled"
It seems like you didn't grant Windows the permission to use your location information. With Maps Pro opened, open the Windows 8 Charms bar (swipe from the right or hover the bottom-right corner with your mouse) > Settings > Permissions and make sure "Location" is toggled on.
My position doesn't change in GPS Direct, it stays at 0
Make sure you selected the right baud rate, check your device specifications. Then uninstall and install again
Do I have to pay for GPS Direct?
GPS Direct wasn't created for Maps Pro and the developer in charge of it recently made some change to the licence. The evaluation licence can be used with no problem for as long as you like but if you would like to support the developer for his app, you can buy a Personal licence on his website.