I think i messed up my arduino

@DouglasDrake
[Edit] Update from which version of grbl?

I don’t use Windows 10, but maybe you could try this for me on your system. I’ve set up an alternative way to upload the firmware and tested on Windows 7. Maybe it will work for you too.

It uses tools from the Arduino IDE, but is stand alone. Use the version of 0.9j that’s included.