About Microsoft's EOP & Compauth Check

Microsoft recently began rolling out a compauth check for Hotmail.com, Outlook.com, and all domains using M365 (formerly known as Office 365).

This authentication check treats all senders as if they had DMARC with p=quarantine on their domain. To clarify, this applies to all domains; those with an appropriate DMARC setup, and those without DMARC at all.

Any sender that doesn't have email authentication in place fails the check, and the email message is placed in the junk folder. In the junk-classed email message, there will be a header with compauth=fail reason=xxx.

You can read more about compauth on Microsofts official website. While that article can help you understand Microsofts updates, what they refer to as SPF is really SPF alignment, and not only SPF on the domain.

Continue reading below to learn how you can set up email authentication for your APSIS One account.


Setting up Email Authentication

We strongly recommend that you set up DKIM authentication.

DKIM has no limitations as to how many domains can be used per account, and it offers email integrity validation, making it the most efficient email authentication solution.

To set up DKIM authentication, simply get in touch with your Account Manager.

Today, DKIM authentication is the only viable solution for APSIS One accounts. However, in the future we will also support SPF alignment. SPF alignment requires that the sender domain matches the from domain. Well let you know once this becomes available for APSIS One accounts.

Setting up email authentication for your APSIS One account will improve your deliverability metrics, ensuring that your newsletters and emails are delivered to as many of your recipients as possible.


Want to learn more?

Take a look at our articles about Deliverability!

Did this answer your question?