You can manipulate COM port assignments in the Windoze Control Panel.
Assign COM 11 to something else, then assign COM12 to COM11.
You could use other ports, as well, if you so choose.
Is there any way to tell what is attaching to a com port.
I am trying to install a usb to serial converter, it installs fine but is using port 12. The device I want to attach only allows a selection up to port 11. So I went to remap the port to something lower and it tells me all ports from 1-11 are in use. I have a couple of serial devices but not enough to use that many ports.
So is there some utility that will tell me what is using them?
Bluetooth adapters, USB-to-serial adapters, USB hubs... They all eat up COM port assignments.
Chances are they aren't actually in use, but asssigned to some device or another.
It's a pain in the ***, but you can likely remove assignments in the Windoze registry for the COM ports that are genuinely not being used. I've had to do that before, although not for my truckPC.