I apparently uploaded a malfunctioning sketch and I am trying to load something over it without success. I have been working through the bootloader before loading process but after I un-comment the bootloader portion of the boards.txt file and restart the IDE, the bootloader version of the board does not show up on the boards list. That makes it difficult to continue with the process.
Zumo 32u4 on Windows 10, Arduino 1.8.6
Thanks