when an event or appointment is longer that 240 minutes the whole appointment book has issues, from ghost appointments showing up, to appointment randomly dropping of the schedule. When we call in for help, the answer is to not schedule longer than 240. But it happens with events also, and many of the people in the office don't understand he problem it causes when they stretch an event to the end of the day, well over 240 minutes and the schedule goes haywire.