Hello, I am using a Craftsman DYT 4000, I was cutting the lawn and suddenly the blade stopped, so I go to pull the red button up, the button which is on the right side, came off, now is this a emergency trip of some sort or the button is broken off, can I glue it back in or not.. thanks, otherwise it was working fine.:(

Hi,
I assume you are referring to the PTO switch knob. If the blade(s) stopped, it does not mean that you needed to pull it up. It could have still been up and stopped for a different reason. At any rate you will have to replace the switch. You can look up the part online at Sears by getting the 9 digit number under the seat and searching for the model. Large plug pulls loose from the back and squeezing the four latches on the switch(two on each of the short sides of the switch -top & bottom, whatever) will allow it to come out of the dash.
Insert new one and plug it in; should only plug one way.
Peace,
Clarke