netsh error: The process cannot access the file because it is being used by another process

It is a server running Windows Server 2016 Essentials. Intuit, in all their infinite wisdom, wanted me to run this command on our file server:

netsh int ipv4 add excludedportrange protocol=udp startport=55368 numberofports=5

The error message I get back is:

The process cannot access the file because it is being used by another process.

So does anyone know what file are we talking about and what process might have it opened?

That error happens if you have already excluded those ports. Confusing error message I know.

Check what you have already using netsh int ipv4 show excludedportrange protocol=udp