I have an older Garmin 35 USB. I plugged it into my laptop and it was not recognized and there appears to be no software or drivers for it. I also do not have an application to check it.
It has been a long time, but it seems when this thing worked in XP I had to install a USB to serial driver or something along those lines, but if you have newer equipment, this may be unnecessary. The software I used the receiver with was Street Atlas USA and at one point an update was required for it to see the Garmin device. If you select a different type of device for the setup, do the allowable ports change?
But if a port was going to show up anywhere, I would think it should be in the device manager. Possibly under USB and then check properties or another entry of some type. You might need to set the view to show hidden devices if it is not listed.
I do not know if additional ports might have to be enabled in your Bios if they are not already.