Sent header details will look a lot smaller than the headers for a received message since it will not consist of the time stamps for the delivery of that message. This is because it hasn’t actually occurred yet. It will only show how it left the original sending server. Everything beyond the sending of the message will be listed on the received message headers.
There isn’t much information needed from these sent message headers. Below is an example when it was sent from DreamHost's test Google account:
The sent info above does not show the various ‘Received’ lines other than the time stamp of when it was sent along with the contents of the message. It does include the message ID Google applied once it was sent so they can track the message, if needed.
Reading bounced or undeliverable notification headers
When messages are sent from a DreamHost hosted email address and that message is rejected, it will look something like this:
The actual bounce error pointing to why the message was rejected is the information at the bottom of the body of the rejection message:
mx1.sub4.homie.mail.dreamhost.com[18.104.22.168] said: 550 5.1.1
<email@example.com>: Recipient address rejected: User unknown in
virtual alias table (in reply to RCPT TO command)
This error message will change depending on why the message was rejected. In this example, the message was sent to a user that does not exist and received a “Recipient address rejected” error.
The headers of the actual bounce notice are not necessary. When troubleshooting rejected email issues, you want to see the original message headers instead to see how the original message was sent. The headers of the rejection will only show you the details of that message rejection email you received.