Forum Discussion
RNalivaika
May 04, 2020Iron Contributor
Exchange Online Protection SPF record
Hi, I have received a message sent via Exchange Online host IPv6 "2603:10a6:20b:c0::31". The message was marked as spam because of SPF fail. Subnet "2603:10a6:20b:c0::/64" is not in the list of O365 ...
PeterRising
May 04, 2020MVP
If you think these messages are being sent by legit Exchange Online senders, then I would say it is the senders responsibility to check and modify their SPF records accordingly to ensure all legitimate entries are included.
- RNalivaikaMay 05, 2020Iron Contributor
PeterRisingsender's SPF is OK
"v=spf1 include:spf.protection.outlook.com -all"
but the IP of the exchange online transport server used was not in the list of host in spf.protection.outlook.com , message header states "protection.outlook.com does not designate 'sample ip here' as permitted sender". BR, Ruslan