Forum Discussion
Exchange Online, DMARC, SPF and Outbound Messages.
Hey Guys, Using Exchange Online here and have some questions regarding Outbound DMARC checking, and Mail-from vs From: address checking for SPF. (All cloud based no local on prem servers). ...
Hi Robert,
1. Office 365 does check DMARC on outbound mail if you set it up. These articles may help to explain why you would do so
https://www.dmarcanalyzer.com/inbound-protection-outbound-control-dmarc/
https://dmarc.org/wiki/FAQ#Why_should_a_Sender_care_about_DMARC.3F
With DMARC, checks are usually implemented inbound and outbound as standard.
2. No, SPF checks the envelope from address, not the From: address. DKIM checks the From Address. The best article for this I find is here which is a series of 3 articles on SPF, DKIM and DMARC
https://blog.returnpath.com/how-to-explain-spf-in-plain-english/
Hope that helps and I have answered your question.
Best, Chris
1. Office 365 does check DMARC on outbound mail if you set it up. These articles may help to explain why you would do so
https://www.dmarcanalyzer.com/inbound-protection-outbound-control-dmarc/
https://dmarc.org/wiki/FAQ#Why_should_a_Sender_care_about_DMARC.3F
With DMARC, checks are usually implemented inbound and outbound as standard.
2. No, SPF checks the envelope from address, not the From: address. DKIM checks the From Address. The best article for this I find is here which is a series of 3 articles on SPF, DKIM and DMARC
https://blog.returnpath.com/how-to-explain-spf-in-plain-english/
Hope that helps and I have answered your question.
Best, Chris
Thanks Chris. Thats so strange becuase On-Prem exhcange servers check mail from, from and HELO. I would have expected EOP to do the same. I guess not. without using DKIM.
Thanks,
Robert