Can anybody explain how Microsoft Outlook implement the unsubscribe button in the header

[nick_shore]

Hi,

I am trying to understand the rules and technical implementation that Outlook uses to show the unsubscribe button in the header of an email next to the sender (image below). I understand they are likely to be implemented by either RFC 2369 or RFC 8058 using the List-Unsubscribe header value I understand there could also be a number of other factors that determine whether or not the unsubscribe button is shown after reading the relevant documentation from Google and Yahoo.

Thanks

Nick

[#2]

Hi @nick_shore,

Microsoft Outlook, incorporates the unsubscribe button in the email header by identifying emails containing a "List-Unsubscribe" header in their metadata.

This header, usually included by the sender to adhere to anti-spam regulations and email marketing best practices, contains a URL or mailto link.Activating this link initiates an unsubscribe request to the sender's server.
Outlook recognizes this header, presenting users with a convenient "Unsubscribe" button as a quick link to this functionality.

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Kindest regards,

Leon Pavesic
(LinkedIn)

[#3]

Thanks @LeonPavesic for you reply.  We send and have been sending our emails for some time now using the List-Unsubscribe header with both the link and mailto specified.  However, as some point they stopped working.  The however work on Gmail and Yahoo mail clients ok.  So there must be additional checks that the outlook client is making when it is deciding whether or not to display the unsubscribe button.

Thanks

Nick

[#4]

Hi @nick_shore,

thanks for the update.

In your case, since the List-Unsubscribe header was working previously and has stopped, it is possible that Microsoft Outlook may have updated its algorithms or criteria for displaying the unsubscribe button. This could include additional checks or changes in how the List-Unsubscribe header is processed.

You may consider reaching out to Microsoft support to resolve your issue of displaying of the unsubscribe button in Outlook.

Please click Mark as Best Response & Like if my post helped you to solve your issue.
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Kindest regards,

Leon Pavesic
(LinkedIn)

[#5]

Yes Leon, thats the reason for raising the question here to see if anyone knew the full criteria required. Do you have or know I can raise this with Microsoft?

Thanks

Nick

[#6]

Hi @nick_shore,

you can contact Microsoft support from your Outlook by clicking on Help > Contact Support

or by going on Contact Us - Microsoft Support

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Kindest regards,

Leon Pavesic
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