Reflexion KBA's
553: Sorry, relay of mail is not allowed
Posted by Robert Mitchell on 07 November 2016 11:45 AM


The error message "#553 sorry, relay of mail is not allowed. (#5. 7.1) ##" indicates that:

  • The smarthost is not configured correctly to send mail via
  • The sending IP of the server is not listed as a trusted host
  • Your IP address may have changed or the IP address you are sending messages from is not in our trusted hosts
  • The sending domain is not sending from a domain listed in Reflexion

You will also see this when you are trying to forward messages to an external domain (ex: or If so, please add the external domains to the permitted relay list:

  1. Log in to Reflexion using your solution provider credentials
  2. Click on Customers
  3. Click on Permitted Relay
  4. Click on New Entry
  5. Add the domain name your customers will be forwarding mail to (ex:, 

*This entry will apply to all of your customers.

Feedback and contact

If you've spotted an error or would like to provide feedback on this article, please use the section below to rate and comment on the article.
This is invaluable to us to ensure that we continually strive to give our customers the best information possible.

(4 vote(s))
Not helpful

Comments (0)
Post a new comment
Full Name:
CAPTCHA Verification 
Please enter the text you see in the image into the textbox below (we use this to prevent automated submissions).

Help Desk Software by Kayako
Copyright 2004-2015 Sophos Limited or one of its affiliates. All rights reserved.