this had been going on for years and I keep forgetting the solution.
I am try to connect my GPs to my Pc. like all modern things it has a bunch of USB ports but no COM port. Those work fine. pluging the GPS in via USB just tells me that the COM port isn’t availible. I know its got something to do with “virtual” COM ports but can’t remember what. Device manager doesn’t help, it just tells me there is a USB cable on a drive be it D to I.
Any ideas?

what gps is it?
COM ports are pretty obsolete these days

My Garmin works fine via USB, I thought that virtual coms ports were a Bluetooth thing. I did need some Garmin drivers installed though so it might be a driver issue for you.

What model of GPS is it?
You need to be connecting through one of these USB to Serialunless it is something like this – USB GPS then it is a soft virtual port which must be installed prior to using. Should be available on the manufacters website.

I thought you were trying to connect to your local GP surgery 😐

Get a serial to USB converter. It comes with device driver software. Goes in the USB port and the Serial GPS Cable plugs into it.

You don’t need to remember any virtual comm bollocks, it does it all.

About £5 of Fleabay.