In the table generated by RecurrenceExpander.Expand() command, value for 'end' column that is same as that of 'start' column. You can confirm the same on the demo page: http://www.daypilot.org/demo/Calendar/RecurrentEvents.aspx Following is the data copied from the demo page: 4/24/2011 3:00:00 PM 4/24/2011 3:00:00 PM Every week MQ==#2#C#T#5#VyAwICo= 1 4/24/2011 10:00:00 AM 4/24/2011 10:00:00 AM Every day Mg==#2#C#U#2011-05-25T10:00:00#RCAqICo= 2 4/25/2011 10:00:00 AM 4/25/2011 10:00:00 AM Every day Mg==#2#C#U#2011-05-25T10:00:00#RCAqICo= 2 4/26/2011 10:00:00 AM 4/26/2011 10:00:00 AM Every day Mg==#2#C#U#2011-05-25T10:00:00#RCAqICo= 2 4/27/2011 10:00:00 AM 4/27/2011 10:00:00 AM Every day Mg==#2#C#U#2011-05-25T10:00:00#RCAqICo= 2 4/28/2011 10:00:00 AM 4/28/2011 10:00:00 AM Every day Mg==#2#C#U#2011-05-25T10:00:00#RCAqICo= 2 4/29/2011 10:00:00 AM 4/29/2011 10:00:00 AM Every day Mg==#2#C#U#2011-05-25T10:00:00#RCAqICo= 2