Query severity of forthcoming O365 Auto-forwarding policy change

Iron Contributor

Roadmap ID 63831 explains how the Outbound Spam protection filter will gain an auto-forwarding control whereby an organisation can prevent auto-forwarding to external addresses. Furthermore, the default setting will be to prohibit rather than permit auto-forwarding (except by mail flow rule).


Does the default posture block existing auto-forwarding arrangements?


If so, that could have quite a big impact on organisations that are still in some disorder following the recent / ongoing pandemic and have not read the Message Center announcements. The new control is already in place and tenants will be switched to the new setting from the 1st September. 

7 Replies

Hi @ExMSW4319 


If the outbound policy is set to Automatic - System Controlled then yes, in September if not action is taken then Auto Forwarding to external domains will be automatically blocked. To ensure existing auto-forwards continue to work, the setting will need to be changed to "On" - for the default policy this will apply to everyone, for a custom outbound policy this will only apply to the users assigned to the policy.




Agree this may cause impact of organisations if they haven't been reading the message centre announcements, but the resolution is a pretty quick change in the portal. 


On the flipside, when we ran through this with a number of our clients they were unaware of some of the auto-forwarding that was occurring and was unable to find a business reason for the forwards, so from their perspective it was a beneficial change that improved security.



@ExMSW4319 To answer your question, as I understand, yes.


"Once the policy takes effect messages that are being automatically forwarded outside the organization will be blocked and non-delivery report (NDR) will be sent to the user."


But they also posted this.


"We understand that some organizations already have users automatically forwarding messages outside the organization and we will provide additional time and communications to enable transition to the new policy controls. For these organizations we will communicate via Message center with more details on when the change will impact your specific tenant."


*edit* Sorry Mark, didn't notice you'd already replied.

Thanks to both posters for your answers.


@ChristianBergstrom- yes, I saw that last line in our Message Center feed and was a bit surprised by it. Are they saying that individual messages will be sent through Message Center to alert tenants as to when the crucial change will occur on their tenancy? I did not know MC could do that.

@ExMSW4319 I believe so. I've seen messages on one tenant that has used a specific feature advising that was going to be retired, but not on another which never used the feature.


I suspect there are all kinds of analytics going on in the background keeping track on how people are using M365. 

Later on Friday an announcement came through our Message Center feed  "...on September 1st, 2020 the Auto-Forwarding Policy will be enforced for tenants who have configured their policy to "On" or "Off", this includes tenants that had users external forwarding prior to September 1st 2020. Your tenant has been identified as having existing users using external forwarding prior to September 1st 2020, and for this reason the “Automatic” setting will default to “on”, i.e. external forwarding is allowed. We will contact you through a separate message center post when the “Automatic” setting will be updated to “off”."



Now we are unable to  find the Roadmap ID 63831  

as we wre getting the error as below for both OOF message or  to external forwarding,


Reason: [{LED=250 2.1.5 RESOLVER.OOF.IntToExt; handled internal OOF addressed to external recipient};{MSG=};{FQDN=};{IP=};{LRT=}]

Reason: [{LED=250 2.1.5 RESOLVER.FWD.Forwarded; recipient forwarded};{MSG=};{FQDN=};{IP=};{LRT=}]


Moro ever we have allowed in anti spam policy or in th remote domains *  also.


Kindly help us