USB Com Ports

I recently bought a USB to RS232 adapter (it works fine). My question is: How can find out which com port it is using, except by trying all of them and then finding the one that works. I have a older Thunderbird GPS 10 MHz frequency standard thet requires a RS232 interface to talk to it (for setup purposes). The first thing it askes me is which com port I'm using(1-16). I have found it by trying one after another until one works, but there must be some way to ask the computer which one it is.
Max Hendrickson


Excellent Member
Microsoft Community Contributor
If you open the Device Manager, do you see anything under the USB controllers that might give you a clue?

Under the view tab, you can change the way the information is presented so as to perhaps give a better idea of your status.

I've got the same problem. Someone on another board said to enable viewing hidden devices and the complainant said that they were now able to see the ports but I'm still not seeing them. I don't see anything under USB controllers that relates to the issue either. The 'Ports' entry should be between Non-Plug and Play Devices and Processors but it isn't there.


Excellent Member
Microsoft Community Contributor
Have you looked for it in Devices and Printers? I can't check since I do not have the device, but if it is listed, see if there are two properties options when you right click. It might allow settings related to com ports.

That's where I am.


Excellent Member
Microsoft Community Contributor
No, you are in Device Manager, not Devices and Printers. If it isn't on the right side of the Start Menu, look in the Control Panel.

Ok, tried that. Not very useful. Don't have a port 0 option.

. Serial Mouse Adapter Properties.PNG


Excellent Member
Microsoft Community Contributor
As I said I do not have you device and cannot check. I thought you were looking for an adapter, not a mouse, but if you are looking at the properties option half way down the right click menu for the adapter, that is all I can suggest.

If you look at the printers, that is what I would expect your device would show. An option to change com ports. Have you installed all the drivers for the adapter?

If you are using it for a mouse, they make adapters that just plug into the mouse to convert it. I may be looking at it wrong. Two devices may be listed on one hub.

Last edited:
The device shows up as a mouse although it is actually a USB to RS232 adapter. When the adapter is plugged in the additional mouse icon shows up. The driver downloaded and installed the first time the adapter was plugged in.

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