How can i obtain UniqueId from MessageId

Question

Hello
I am sending a mail message using SMTP and Rebex, I am getting the messageId while sending email and storing it in my database, but later on i want to know if it is delivered or not. i can see that you have a class named delivery-status for it, but i cant find the sent mail from imap with messageid, it requires sequenceid or uniqueid, which i dont have them.
I have only messageId and envelopeId which are the same for me.
How can i obtain uniqueId using messageId?

Answer 1

Hello,

Unfortunately, it's not that simple in IMAP. IMAP protocol's unique ID has no relation at all to MessageId or EnvelopeId. To make it even more complicated, a delivery status notification (DSN) is not actually a response, and can't be searched for using MessageId or EvenlopeId. Overall, there is no straightforward way to simply obtain a unique ID of a DSN based on the message ID.

Instead, a different process is usually used: The application checks Inbox for new messages. For each new message, it determines whether it's a delivery status notification. If it is, the application parses it and tries matching the DSN against known MessageId or EnvelopeId of a sent messages.