Hi.
I have several ArduinoMKR1ooo boards and has been uploading code successfully to one of them several times, but suddenly it does not work anymore.
The port under File / Port is most often grayed out, just like its an unstable USB port.
After trying several times I will often see the port again and can start uploading/evaluating the code, It always almost finish and then fails with the words: "Couldn't find a Board on the selected port", and quite correct the port is not visible anymore.
I have uninstalled & reinstalled the USB plugs, and they are more than stable enough for other boards like Arduino Uno. And since I have been testing on 3 MKR1000 cards, I know it's no problem with the card itself.
Thanks for any advice