Bounceback: "501 Connection rejected by policy [7.2]"

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Article ID: 170004

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Updated On:

Products

Email Security.cloud

Issue/Introduction

Users are receiving a non-delivery receipt (NDR) when sending an email to a Symantec Email Security.Cloud customer.

501 Connection rejected by policy [7.2], 
    please visit www.messagelabs.com/support for more details about this error message

Cause

The sender IP address has been listed in third party email blacklist.

Environment

Email Security.cloud

Resolution

The sender administrator would need to check their IP and request delisting from any blacklists.

Once the IP has been removed from these lists, the sender domain can try to send the email once again.

The following sites could be used to check for any blacklisting: