Gmail Messages Blocked

The 550 5.7.1 … lacks SPF/DKIM/DMARC Auth Records (AS9031519) response is a server-level rejection before the message reaches your Hotmail mailbox, so adding Gmail addresses to Safe senders cannot override it.

Determine which side must resolve it

1. From Gmail on the web, send a new test message to the Hotmail address.
   • Select the From field.
   • Ensure it is the sender’s actual @gmail.com address—not a custom-domain address, alias, “send mail as” identity, mailing list, or forwarded address.
   • Keep the complete bounce message if it fails again.
2. If the From address is a custom domain or alias, give the complete bounce to that domain’s administrator or email provider. They must check the sending domain’s SPF, DKIM, and DMARC configuration and alignment. Those records belong to the sender’s domain and cannot be repaired from your Hotmail account.^1^
3. If the From address is a normal @gmail.com address sent directly through Gmail, neither Gmail users nor Hotmail recipients manage the authentication records for gmail.com. With the same AS9031519 rejection recurring, report it to Outlook.com Support as a potentially incorrect authentication verdict.^2^

Contact Outlook.com Support

While signed in to the affected Hotmail account:

1. Select Help on the Outlook.com top menu.
2. Search for AS9031519 Gmail rejected.
3. If the suggested articles do not resolve it, scroll to Still need help?
4. Select Yes and submit the case.^3^

Include:

• The complete error: 550 5.7.1 Message rejected: Message lacks SPF/DKIM/DMARC Auth Records (AS9031519).
• The Outlook protection-server hostname and UTC timestamp from the bounce.
• Confirmation that it was sent directly from an actual @gmail.com address using Gmail.
• Whether multiple unrelated Gmail accounts receive the same rejection.
• The screenshot, with all personal email addresses obscured.

Safe Senders only prevents successfully delivered messages from being moved to Junk; it does not affect mail rejected during the sending server’s connection.^4^ No further changes to that list are needed.

As a temporary workaround, use another receiving address until Microsoft or the custom-domain sender corrects the authentication rejection.

References

1. Security Operations guide for email authentication in Microsoft 365
2. Incoming emails rejected – Error AS9031519 - Microsoft Q&A
3. How to get support for Outlook.com | Microsoft Support
4. Safe Senders in Outlook.com | Microsoft Support