What's an NDR and why have I received one?

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Non Delivery Report (NDR): Why do my emails bounce back?

Posted on 20 February 2017 by Beaming Support

Are you getting a ‘bounce back’ (NDR) message due to your email being marked as spam?

Occasionally you may find that your emails bounce back and you receive Non Delivery Reports (NDRs) saying that your email has been caught in the recipient’s spam filter, or you may find a lot of senders’ emails are going to your own spam filter.

Most of the time the NDR will notify you of exactly why your message has been quarantined with an explanation in plain text or even an error code.

There are many different reasons as to why this happens, however for this blog post we’ll cover the main culprits when emails bounce back: hyperlinks, weblinks and embedded images.

Hyperlinks, weblinks and embedded images can cause issues when the underlying host server for the link has been marked on one or more spam databases. This then causes any email that includes this link to be marked as spam.

For example, say your email signature has a link (or image with a link) to your company Facebook, Twitter or LinkedIn profile and any of those providers use a host whose server is identified as sending spam then this will also affect your email you are sending/receiving.

Unfortunately there isn’t much as an end user you can do until the offending server has been removed from that spam database. The best way to test, or temporarily get around the issue however is to remove the underlying links for images or hyperlinks within your email.


NDR – Non Delivery Report/Receipt
DSN – Delivery Status Notification
NDN – Non Delivery Notification


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