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Composite Authentication Question
All,
I sent a test email to myself in my Office 365 Work Email Box. I look at the headers and discover my compauth=other with reason=501. What does this mean?
I sent a test email to myself in my Office 365 Work Email Box. I look at the headers and discover my compauth=other with reason=501. What does this mean?
2 Replies
You can read about Composite authentication here: https://docs.microsoft.com/en-us/office365/securitycompliance/anti-spoofing-protection#composite-authentication
- Neither that page nor the "Anti-spam message headers in Microsoft 365" page that it references says anything about compauth=other nor reason=501.
