Hi,
I was having problems with uploading sketches to Arduino MKR Vidor 4000. I would like to share with you my experience.
Appart of what I am doing in the video I also had to make a clean installation of Arduino IDE 1.8.7.
I had to remove all the instances of Arduino from:
c:\users\YourUserName\AppData(hidden folder)\Local\Packages
also
..My Documents\Arduino\libraries\
After unpacking an Arduino IDE 1.8.7, I only installed the board.
At first, I was able to upload the sketch and Vidor was working. After first upload it was dead. It took me 3 days to work it out, so if you want to save your self a bit of time, just watch the video. I still don't know why it is doing it.
Sometimes I can upload the sketch without pressing the power button twice. Sometimes I can see COM Port 9 and 15, sometimes only 9 or 15. It just does whatever it wants at the moment.