Question UCCNC D840 E-Stop

I just set up my new D840 and ran the Stepcraft logo with no problem. I loaded a file from VCarve Pro that I created but am having issues. The first run started great but then failed at the end. I stepped away for a day and went back at it again. The second time I ran a dry run with the spindle off. Everything ran grate. when I turned on the spindle, that's when it went wrong again. The job stopped abruptly stating an e stop.

Why would the spindle running cause the UCCNC to stop the program?