Category: dkim
-
Message Header Analyzer and Double DKIM
Update – Microsoft fixed this issue after I reported it to them If you have SMTP email routing that goes through multiple systems, and more than one of these stamps a DKIM header you should get dkim=pass at the receiver. But if one of these email servers modifies the message body then DKIM for all…
-
Improving Exchange Online Email Deliverability Through Third Party Filtering Services – Trusted ARC Sealer
When you receive emails into Exchange Online and you filter the external messages before arrival with a third party filter such as Mimecast, Proofpoint or others, then you can have DMARC failures that result in messages being junked or quarantined in Exchange Online. Trusted ARC Sealer is a feature of Exchange Online to allow you…
-
DMARC Quarantine Issues
I saw the following error with a client the other day when sending emails from the client to any of the Virgin Media owned consumer ISP email addresses (virginmedia.com, ntlworld.com, blueyonder.com etc.) mx3.mnd.ukmail.iss.as9143.net gave this error:vLkg1v00o2hp5bc01Lkg9w DMARC validation failed with result 3.00:quarantine In the above, the server name (…as9143.net) might change as will the value…