Forum Discussion
Incomplete SPF record for O365?
I've an odd email SPF issue. I'm receiving email from an organisation with O365 hosted mailboxes to an organisation not hosted in O365. The non-O365 organisation is correctly rejecting quite a lot ...
'In certain scenarios, messages that are forwarded or relayed via Microsoft 365 are sent using a special relay pool, because the destination shouldn't consider Microsoft 365 as the actual sender... This address pool isn't published because it can change often, and it's not part of published SPF record for Microsoft 365.
The forwarded or relayed message should meet one of the following criteria to avoid using the relay pool:
- The outbound sender is in an accepted domain.
- SPF passes when the message comes to Microsoft 365.
- DKIM on the sender domain passes when the message comes to Microsoft 365.'