Forum Discussion
Unverified Sender Messages Highlighted By Outlook Mobile
Outlook Mobile clients have started to highlight messages received from unverified senders. But what does “unverified” mean and what can be done to fix the problem? The issue lies at the sender’s end, so the administrators of the sending system must verify their email configuration to make sure that Exchange Online can validate inbound messages from their domain. The same visual markers are available in Outlook classic, OWA, and the new Outlook.
https://office365itpros.com/2025/08/19/unverified-sender-outlook/
2 Replies
No. It's a transport thing. However, tenant administrators can make it less likely that their outbound email is marked as unverified by making sure that their SPF, DKIM, and DMARC configurations are correct.
Unverified: Could it be that the email administrator or the server failed to properly identify the sender of this email (meaning the security verification did not pass)?
