TO DO THIS, YOU MAY NEED TO TAKE THE METAL COVERING OFF FROM AROUND THE SPINDLE.
The air actuated cylinder that bring the dust hood up and down, there is a little black sensor with a red coloured LED on it. Make sure when the dust boot is in the UP position, that little black sensor's red LED light is illuminated.
Right now your machine is not noticing if the dust boot is up or down, which is causing this error. 
If you look under the metal spindle cover, you will see the little black coloured sensor with its red LED either illuminated or not:
Red LED illuminated:
With the dust boot physically in the UP position (do so by using the Dust Boot button in the MDI screen of the Masso controller), move the black sensor down a little bit and tighten it. By lowering that sensor a bit, see if it fixes the dust boot error issue.
Was this article helpful?
That’s Great!
Thank you for your feedback
Sorry! We couldn't be helpful
Thank you for your feedback
Feedback sent
We appreciate your effort and will try to fix the article