How do I know if mail is forwarded mail?

Question

I have a particular problem.

If we create mail in Outlook, we add a UserProperty, which contains the database identifier of our system, so we can associate mail with the representing DataBase element. In a service that reads letters in each mailbox and automatically imports them, I can read this property using ExtendedPropertyDefinitions. So far so good ...

If the user now forwards the message to Outlook, Olk copies UserProperty to the new message. And now my problems begin. Now my service considers that the new message is also related to our database and updates the DB-Entry with the new Body and the new Subject.

So anyone now, how do you know if a message is forwarded or how to tell Outlook not to copy a custom property into a forwarded (new) message?

THX Jay

What we thought about, but it doesn’t work for our business,
is the second user property containing a simple link from the "fromSystem" tag. Because it will also be copied.
- a second user property containing a hash calculated from the subject and the Body. Because both can be changed by the user. We simply create a message, add all the properties and display it. from this point we no longer control what happens to the mail until the Service processes it.

Answer 1

EWS ConversationIndex , 22 ( ). 5 (10 ) ConversationIndex, 22 .

Original: 01CDD15D80E51C1D4522172840ACA96287DA28A15D97
Reply:    01CDD15D80E51C1D4522172840ACA96287DA28A15D970000018630
Forward:  01CDD15D80E51C1D4522172840ACA96287DA28A15D970000018630000000FC30

ConversationIndex ConversationTopic ( , GUID + ). . MSDN. ConversationIndex MSDN .

 

 if (message.ConversationIndex.Length == 22)
 {
   // update DB body, subject, etc.
 }

, EmailMessageSchema.ConversationIndex, .