Fix Office 365 forwarding error Your message wasn’t delivered because the recipient’s email provider rejected it.

I used to have an auto forward set up on my mail account in Office365. However, since a few weeks I encountered the following errors:

Your message wasn’t delivered because the recipient’s email provider rejected it.


Remote Server returned ‘550 5.7.520 Access denied, Your organization does not allow external forwarding. Please contact your administrator for further assistance. AS(7555)’

The result of these error messages was that my emails were no longer automatically forwarded to another mailbox.

Remote Server returned '550 5.7.520 Access denied

What causes this error Remote Server returned ‘550 5.7.520 Access denied’?

Before September 2020, Office 365 allowed emails to be automatically forwarded to external email addresses. This is called “External forwarding”. However, since September 2020, a setting has been changed, whereby External Forwarding is disabled by default at the organization level. This means that all mail that was previously neatly forwarded to an external email address is now suddenly blocked. The affected mailbox, the mailbox with the forwarding rule set up, receives the error “Your message wasn’t delivered because the recipient’s email provider rejected it.

How to fix Remote Server returned ‘550 5.7.520 Access denied

An Office 365 administrator can adjust the default setting in the Office 365 environment, making it possible to forward mail externally again. If you are a user of Office 365, please ask your IT Admin to adjust the setting and send him or her the URL of this web page.
If you are an administrator, follow these steps to re-enable External Forwarding:

  1. Go to the Office365 Security and Compliance Dashboard
  2. Expand Threat Management and click Policy
  3. Click Anti Spam
  4. In the Anti-Spam settings, locate Outbound spam filter policy (Always ON) and click Edit policy
  5. In the Outbound spam filter policy, expand Automatic Forwarding. The default is set to Automatic – System-controlled.
  6. Select On – Forwarding is enabled and click Save. Forwarding to external mail addresses is now allowed. Note Microsoft says it may take up to 24 hours before the change takes effect. Although it took 5 minutes in my case :)

A setting to rethink – Automatic Forwarding to external email addresses

You may wonder whether it is a good idea to change the default setting for automatic forwarding to external addresses.
One reason for not allowing it is data loss prevention. Recently I was with a customer whose password had been leaked. Hackers have gained access to his mailbox. Instead of directly using his mailbox, they set – unnoticed – a rule that automatically forwarded all mail to an external email address. A good example of corporate espionage.

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This still works; some of the original words associated with some of the things to click on have varied a bit, but not enough that you can’t figure it out. The end result worked just fine.


I have problem after click save

Exception of type ‘Microsoft.Exchange.Management.PSDirectInvoke.DirectInvokeCmdletExecutionException’ was thrown.


THANK YOU!!!!!!!!!!! I’ve spent forever trying to fix this!!! It worked!


I cannot access Office 365 Security and Compliance Dashboard. How else can i fix this??


John van Ooijen, can you help all of us who have done what you blogged but are getting the other error messages?
Can someone share the solution as getting the
 run the command: Enable-OrganizationCustomization

If we can get all the steps for downloading the powershell to configuring after and so on, that would be helpful.


Can someone share the solution as getting the
 run the command: Enable-OrganizationCustomization

Wayne Smith

Now I get the error that I must enable organization customization. Frankly, I am lost! Can someone advise how to enable organization customization? thank you

Lee Woolsey

Same here! Any advice please?


I am not sure if this is the right way, but I managed to adjust it by going to Here I gave myself the role in Organization Management. Now I can adjust the forwarding error, but somehow I still get an error. But maybe I have to be a little more patient ;)


Super Awesome! Thanks


changes have been saved, On – Forwarding is enabled
but why are my emails still undeliverable to one specific recipient? I rebooted my computer after all the steps


have you found the solution yet ? i have the same issue with you. I hope your solution :((


i am vietnamese too :((


This did the trick thank you!


Wow, thanks so much!!


Thank you – gr8 tip


Huge Help, Thanks

Andrew Knight

Thank you.


Noice, very noice


Thanks for this very carefully composed and thorough explanation as to how to de-fang this completely sick default setting. MS did it, but reported it as if the remote server was responsible. I’m struggling to refrain from using profanity.


Thank you, from Chile :)


Thank you

Andrey Kravchenko

Man! Thanks a lot. You my hero!))

Jim Ryan

Thanks, but I can’t seem to save it. I am admin. Doing it in Chrome.

Chris Scott

Another quick thank you for posting this, at least its a quick fix.


Thnx a lot for the solution


Thanks for sharing. However, it goes back to “Automatic – System Controlled” when i save and close the window


thanks for the solution!

How can we apply on an individual user?

Ulrich Pieper

thx man


Thank you figuring this out and sharing the solution


Thanks this article saved our ticketing system workflow.


Many thanks !!!

Kelly C.

Thanks for this – I had rule with exceptions within the exchange admin and it stopped working on Friday. If I change this to On, will the rules then pick up again and the exceptions still work or is there another way to do this?

Anna G

Thank you! Finally the mystery is resolved!



Kamia Khatun

Thank you so much for sharing the solution..

Yonatan Cruz

Excelente, muchas gracias.


So what if you want it disabled by default but need exceptions :)

Victor Chen

worked like a charm, thanks for the post!

K. Collier

Perfect timing… I was pulling my hair out with this problem yesterday and today! Thank you so much for sharing the solution… I never would’ve found it.

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