After upgrade, ServiceNow add new email header.

[tuitendung]

Emails with Reports are going into Junk folder after instance upgrade. I found a new header added in the SNOW emails (List-Unsubscribe). When this header is detected, an Exchange mail flow rule increases the spam score. Can I do anything to detect it before upgrade or an upgrade activity to be added to compare and prevent issue before upgrading.

[Maik Skoddow]

There is no configuration option in ServiceNow for email headers as those are added by the email server outside of ServiceNow. Please raise a case in the support portal to address the issue.

[Ben Sweetser]

We ran into this, too, and my colleague discovered a solution on the support site. You need to be signed in to see the content, so I'm posting the text here to save you some time. We tested the property to remove it and it worked:

Instructions
This is a new functionality in Washington: Unsubscribe with one click. There is a property that we can use to disable it, but the documentation doesn't provide information about it.

From the documentation: Email unsubscribe

Unsubscribe with one click: Unsubscribe from email notification using a one click approach. You can directly unsubscribe form notification emails by selecting Unsubscribe next to the email address. An unsubscribe request goes through and a pre-formatted email message is automatically sent.

*Important: Unsubscribe with one click is supported from Washington Patch 1 onwards.

Set the glide.email.one_click_unsubscribe.enable = false to disable this feature:
1- Open the sys_properties table
2- The property doesn't exist, so you have to create it.
3- Save the form.
4- Test your notifications.