Mine locks up on the error box telling me a value is no good. I can't close the box, I can't change the value, I can't get back to the main Mach3 screens and I can't use CNTRL ALT DEL to kill Mach3. I'm stuck forcing the computer off. Had to kill it 3 times before I figured out all the items that had to be set. Reminds me of my old Quickbasic days with loop errors.