I’m taking over a project from someone else. I’ve been given an Uno and a Pro Micro that have already been programmed and apparently worked fine. However, when I plug either one into my MacBook Air, my laptop doesn’t recognize them - nothing new appears in the list in Arduino => Tools => Ports. I also tried both of them with a friend’s PC and the same is true there. Is there something the previous person using these boards might have done that is preventing them from appearing in the serial ports list?