Microsoft and SPF

Many deliverability folks stopped recommending publishing SPF records for the 5322.from address to get delivery to Microsoft. I even remember Microsoft saying they were stopping doing SenderID style checking. A discussion on the emailgeeks slack channel has me rethinking that.

It started out with one participant asking if other folks were seeing delivery improvement at MS if they added a SPF record for the 5322.from. Other folks chimed in and said yes, they had seen the same thing. Then I started digging and discovered that MS is still recommending SenderID records on their troubleshooting page.

Email sent to Outlook.com users should include Sender ID authentication. While, other forms of authentication are available, Microsoft currently only validates inbound mail via SPF and Sender ID authentication.

Microsoft Sender Support

The support page may be out of date, or it may not. In any case, it may be worth adding a SPF record to your 5322.from domain if you’re seeing persistent problems at Microsoft and no where else.

This isn’t great practice overall. But, it may explain why some folks are having such a hard time cracking the MS inbox.

Related Posts

Null sender address

A question came up on the email geeks slack channel about empty from addresses. I asked if they meant the 5321 or 5322 from address which prompted a question about if you could even have a null 5321 from.

Read More

SenderID is dead

A question came up on the email geeks slack channel (Join Here) about SenderID. They recently had a customer ask for SenderID authentication.

Read More

Fun with opinions

Over the last few weeks I’ve seen a couple people get on mailing lists and make pronouncements about email. It’s great to have opinions and it’s great to share them. But they’re always a little bit right… and a little bit wrong.

Read More