And that, my friend, is true wisdom! 
But as well, it might be useful to know that in Windows, in Device Manager, under “Sound, video and game controllers”, you’ll find the device “Steinberg Midex 8 USB Midi Driver”. If you right-click that and select Properties, on the Settings tab you can also enable or disable individual ports system-wide. This can be useful to disable ports that you don’t have connected – they won’t show up in applications such as Cubase, and possibly make for a less cluttered setup. You just have to remember where this setting is if you ever need to re-enable them!