Undeliverable emails will look similar to this:

From: System Administrator
Sent: Monday, October 30, 2017 3:44 PM
Subject: Undeliverable: test

Your message did not reach some or all of the intended recipients.

Subject: test
Sent: 10/30/2017 3:43 PM

The following recipient(s) cannot be reached:

'example@otc.edu' on 10/30/2017 3:44 PM

This message could not be sent. Try sending the message again later, or contact your network administrator. You do not have the permission to send the message on behalf of the specified user. Error is [0x80070005-0x0004dc-0x000524].

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