Error on reading a Calendar Appointment, sent by ExchangeService RRS feed

  • Question

  • Hi all,

    I have used Microsoft.Exchange.WebServices.ExchangeService to send appointments to some emails as below:

            ExchangeVersion exchVersion = new ExchangeVersion();
            exchVersion = ExchangeVersion.Exchange2010_SP1;
            service = new ExchangeService(exchVersion);

            service.Credentials = new WebCredentials(userName, password, domain);
            service.ImpersonatedUserId = new ImpersonatedUserId(ConnectingIdType.SmtpAddress, email);

           Appointment meeting = new Appointment(service);

            meeting.Subject = Subject;
            meeting.Body = new MessageBody(BodyType.HTML, htmlBody);
            meeting.Start = StartTime;
            meeting.End = EndTime;
            meeting.Location = Location;
            foreach (string email in Emails)
                Attendee at = new Attendee();
                if (!string.IsNullOrEmpty(email))
            return meeting.Id.UniqueId;

    But some users can not open the calendar and get this error:

    "The operation failed. The messaging interfaces have returned an unknown error. If the problem persists, restart Outlook."

    There is no problem for most of users but some. can any any one help?

    Wednesday, December 19, 2012 12:19 PM