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Email “Undeliverable” or “NDR” Messages

What are these messages?
It is possible for errors to occur at multiple levels in mail delivery. A sender may at times receive a bounceback message from their own mail server. While other times a sender may receive a bounceback from a recipients mail server. Bounce-back messages from the recipient’s mail server are required when a mail server accepted a message that was undeliverable; when a server accepts a message for delivery, it is also accepting the responsibility to deliver a DSN in the event the delivery fails.

Why might I receive them commonly?
With the rise in forged spam and e-mail viruses, users now frequently receive erroneous bounce messages sent in response to messages they never actually sent. Modern servers try hard to ascertain that a message can be delivered before they accept it.

What can I do to assure mail is sent without error?
Always start by ensuring the email address of the recipient is accurate. This tool may be used to confirm the address you are attempting to reach exists and is valid. If the mailing address is confirmed to be valid, you may send us a copy of the bounced delivery report. We will then attempt to isolate and resolve the cause of the bounceback.

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