I am running the latest Arduino IDE 1.8.8 on a Windows 10 machine. I bought a Arduino Uno a month ago and my system was working fine as expected. Yesterday I added a MKR1000, loaded drivers through the board manager. I can load sketches into the MKR1000, they run fine, but I can not see the serial monitor window. If I press ALT Tab in Windows 10, I can see that a serial monitor window is running, but when I select it, it remains closed. I tried deleting and reloading the MKR1000 drivers, but that did not help.
Now even with my Arduino Uno, I am not able to open the serial monitor any more.
How do I get the serial monitor back?