Adding distribution lists and email reports as attachments using Exchange EWS managed API.

I am not able to send a mail which has a email report (read/delivery... receipts) and distribution list as an attachment. I am using the AddItemAttachment<> API as mentioned in the sample application present on MSDN.

For example I tried  the following ways -

• When I try to use ContactGroup as the template class in the method, it fails with the error -"Items of type ContactGroups are not supported as attachments" , when I call the final SaveAndSend.

EmailMessage email = new EmailMessage(service);
email.ToRecipients.Add("user@contoso.com");
ItemAttachment<ContactGroup> itemAttachment = email.Attachments.AddItemAttachment<ContactGroup>();
email.SendAndSaveCopy();

• If I try to add the attachment with the Item class as the template class  and then manually change the message class, it fails with the error-"Operation would change object type, which is not supported", when I call the final SaveAndSend. I have also tried to set the extended MAPI property PR_MESSAGE_CLASS
  

EmailMessage email = new EmailMessage(service);
email.ToRecipients.Add("user@contoso.com");
ItemAttachment<Item> itemAttachment = email.Attachments.AddItemAttachment<Item>();
itemAttachment.Item.ItemClass = "IPM.DistList";
email.SendAndSaveCopy();

• If I try add the attachment with the Item class and then do not manually change the the class, the final SaveAndSend succeeds but the attachment is created as a sticky note.

EmailMessage email = new EmailMessage(service);
email.ToRecipients.Add("user@contoso.com");
ItemAttachment<Item> itemAttachment = email.Attachments.AddItemAttachment<Item>();
email.SendAndSaveCopy();

I am facing a similar problem with email reports (I use method 2 and try to change the message class manually). I am using Exchange 2013 CU2 on a Win 2012 server. Can someone suggest the correct method?

Thanks.

- NYA