I have a C API application that creates calendar events in a standard mail template database. I am creating a meeting event, and seem to have the Chair, altChair, required attendees, etc. all set correctly. The event looks fine in the Notes client. However when I try to change the attendees, i.e. delete or add any, then save the event, I get the error message “An error occurred while saving: Note item not found”. I have seen the discussion about $CSVersion and I have it set to 2. I can’t see any significant difference between my created entry and a Notes native entry (which can be modifed without problem). Any ideas what I need to do to avoid this problem?