Email Redirection from Office 365 not being deliverered/process by Sophos Central Email Gateway

Hello All, 

This issue started last week for us. I have a mailbox that redirects all emails to an external email address. Somehow this completely stopped. I am seeing the following

NDR See screenshot below. Is anyone experiencing this issue or able to replicate? I have tried to create another redirection rule on another mailbox same result. I tested with another  0365 tenant that is not using Sophos Central Email Gateway and I am able to receive the redirected email without an issue. Bypassing the Sophos Outbound connector also delivers the email without an issue. Can someone help confirm this is an issue?


Error: Reason: [{LED=550 5.7.1 Command rejected};{MSG=};{};{IP=};{LRT=6/18/2020 1:24:48 PM}]. OutboundProxyTargetIP: OutboundProxyTargetHostName:


  • Hello Ninjatech1969,

    Thank you for contacting the Sophos Community!

    May know, how is your mail flow?

    What email is being involved in the redirection and to which email address is O365 sending the redirected email?

    I guess you must have some type of Distribution List in Sophos Central? 

    Is your email flow something like this  Inbound email >> Sophos Central = Mailbox >> O365 >> 0365 redirectes to External email address >> Sophos Central >> Redirected Email box?


    Emmanuel Osorio  

  • In reply to emmosophos:

    This is exactly my flow .>> Sophos Central = Mailbox >> O365 >> 0365 redirectes to External email address >> Sophos Central >> Redirected Email box?..

    If i remove the SC external connector emails redirects just fine so I know it is stopping from the Sophos side

  • In reply to Ninjatech1969:

    In general, Central Email will block redirections from an internal email to an external email to prevent being a relay. There are a few exceptions, such as O365 meeting invites which are resent from a protected email address. 

    I hope this answers your question.

    If you want to propose changes to how the product works - please submit them at

  • In reply to RichardP:

    What does in General means...Did something change from your end. This was working fine all year??

  • In reply to RichardP:

    This was working all year you are telling me this isn't supported. this doesnt make sense