Situation: A user creates a recurring event, this user deletes a single instance of the recurring event.
Goal: recover/restore the deleted instance to the calendar. Though actually I really just need to report on the cancelled instance (i.e. I look at a particular day for a user's calendar, how many meetings were cancelled vs scheduled).
For single appointments, when I do a MoveToDeletedItems delete or cancel action I can find that event in the DeleteItems folder and Move it back to the calendar or report on it.
However, occurrences of recurring series are treated differently. It seems like deleted occurrences (and all their data) are permanently deleted and the only trace is in the RecurringMaster.DeletedOccurrences but that only stores a OriginalStart property not title/description/attendees/etc.
All I figure I can to do is to merge info from the master recurring event (title/description/etc) with the original start to get a "deleted instance" appointment. Is this true? Note: this won't recover the right information if the instance was an Exception to the RecurringMaster appointment.
Note: this works pretty much the same for ews versions 2007 to 2013 (Office365)
Search terms: restore recover deleted cancelled instance occurrence recurring series recurringMaster DeletedOccurrences DeletedItems