I was setting the calibration on my X-axis. I have done this numerous times before. The feedrate was set very low. I entered the desired movement distance, the machine slowly moved in the positive direction, I entered the actual movement distance, OK'd the new setting and tried a new distance to confirm the calibration. This time my machine took off in the negative direction so fast I barely saw it, let alone had time to hit the E-stop. It smashed into my proximity limit switch so fast the switch got destroyed before it could stop the gantry. The movement had to be more than 10 times what I had entered, and in the wrong direction.
As no other settings had been touched between these two events I figured there must be something going on in the software itself. I then downloaded a fresh version of Mach3 and installed it under a different directory on my computer. Doing that somehow turned both the original and the new one to demo versions.
Has anyone ever had either of these things happen?