public string UpdateAppointmentInCrm(Outlook outlookId)
        {
            Trace.TraceInformation("UpdateAppointmentInCrm");

            if (!InitializeHelpers())
            {
                return("Initialize helpers fail");
            }
            List <AttendeesResponse> responses = exchangeHelper.GetResponseStatus(outlookId.outlookId);
            var appointmentEntity = exchangeHelper.GetAppointmentFromOutlook(outlookId.outlookId);

            appointmentEntity.CrmId = crmHelper.GetCrmIdByOutlookId(appointmentEntity);
            crmHelper.UpdateResponsesInCrm(appointmentEntity, responses);
            return("UpdateAppointmentInCrm success");
        }