Get the Body from an appointment with the EWS API

Hello,

wrote some code to export the whole calendar for each user in a distribution group as an ics File.

My problem is tha I am not able to export/write the Body of the appointment in the ics file. I get:

"You must load or assign this property before you can read its value.".

If I bind every appointment after I have searched every Calendarfolder to get the Body it takes hours to generate the ics files.

Here is my code:

            //Instantiate the ExchangeService class+ Exchange Certificate Validation + Impersonator
            ServicePointManager.ServerCertificateValidationCallback = CertificateValidationCallBack;
            ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2010_SP2);
            service.Credentials = new NetworkCredential("user", "password", "domain");
            service.AutodiscoverUrl("impersonator@domain", RedirectionUrlValidationCallback);

            //Distinguish Distribution Group
            string distributiongroup = "distribution@domain";

            // Initialize values for the start and end time.
            DateTime startDate = DateTime.Now.AddDays(-10);
            DateTime endDate = startDate.AddDays(180);

            //Extend the distribution group
            ExpandGroupResults distGroupMembers = service.ExpandGroup(distributiongroup);
            foreach (EmailAddress address in distGroupMembers.Members)
            {
                //Impersonate each distribution group member
                service.ImpersonatedUserId = new ImpersonatedUserId(ConnectingIdType.SmtpAddress, address.Address);

                //Create iCalendar and add local time zone
                iCalendar iCal = new iCalendar();
                ITimeZone localTZ = iCal.AddLocalTimeZone();

                // Build a list of additional time zones (local time zone is allready included)
                List<ITimeZone> otherTimeZones = new List<ITimeZone>();
                foreach (TimeZoneInfo tzi in System.TimeZoneInfo.GetSystemTimeZones())
                {
                    if (tzi != System.TimeZoneInfo.Local)
                    {
                        // Add the time zone to our list (but don't include it directly in the calendar).
                        otherTimeZones.Add(iCalTimeZone.FromSystemTimeZone(tzi));
                    }
                }

                //Path and Filename for ics File
                string icsFileDirectory = @"C:\\Users\\ikyriakidis\\Desktop\\ICAL\\";
                string icsFileName1 = address.Address;
                string icsFileName2 = ".ics";
                string icsFileName = icsFileName1 + icsFileName2;
                string icsFile = Path.Combine(icsFileDirectory, icsFileName);


                //Set reminder for the Meetings/Events (5 minutes befor event)
                Alarm alarm = new Alarm();
                alarm.Action = AlarmAction.Display;
                alarm.Trigger = new Trigger(TimeSpan.FromMinutes(-05));


                // Execute the search in the calendar folder and return the view
                CalendarView cView = new CalendarView(startDate, endDate);
                cView.PropertySet = new PropertySet(BasePropertySet.FirstClassProperties);
                FindItemsResults<Appointment> apt = service.FindAppointments(WellKnownFolderName.Calendar, cView);

                foreach (Appointment app in apt)
                {
                    //Appointment appDetailed = Appointment.Bind(service, app.Id, new PropertySet(BasePropertySet.FirstClassProperties) { RequestedBodyType = BodyType.Text });
                    //Create event in ical
                    Event iCalEvent = iCal.Create<Event>();

                    //Set the event papameters
                    iCalEvent.Summary = app.Subject;
                    //iCalEvent.Description = app.Subject;
                    iCalEvent.Description = app.Body.Text;
                    iCalEvent.Start = new iCalDateTime(app.Start);
                    iCalEvent.End = new iCalDateTime(app.End);
                    iCalEvent.Duration = app.Duration;
                    iCalEvent.Location = app.Location;
                    if (app.IsReminderSet == true)
                    {
                        alarm.Description = "Reminder";
                        iCalEvent.Alarms.Add(alarm);
                    }
                    if (app.Sensitivity == Sensitivity.Private)
                    {
                        iCalEvent.Summary = "privater Termin";
                        iCalEvent.Description = "privater Termin";
                        iCalEvent.Location = " ";
                    }
                }



                //Create ics File
                iCalendarSerializer serializer = new iCalendarSerializer(iCal);
                if (!Directory.Exists(icsFileDirectory))
                {
                    Directory.CreateDirectory(icsFileDirectory);
                    serializer.Serialize(icsFile);
                }
                else
                {
                    serializer.Serialize(icsFile);
                }


            }


        }

Whene I replace the "iCalEvent.Description = app.Body.Text;" with "iCalEvent.Description = app.subject;" and comment out the "Appointment appDetailed = Appointment.Bind(service, app.Id, new PropertySet(BasePropertySet.FirstClassProperties) { RequestedBodyType = BodyType.Text });" it takes no more than 90 seconds to generate all the ics files!

Can you please help me on this one.. I have been strugeling for days to make it work...

Thank you.

Ioannis