Subject and body are blank when sending S/MIME emails in Outlook for Mac

Last Updated: September 10, 2025

ISSUE

When you manually encrypt an email with S/MIME and send it, you find that the subject and body are blank.

STATUS: FIXED

This issue is fixed in build 16.100.4.

WORKAROUND

To work around the issue, enable the setting Always encrypt outgoing messages.

Additional Information

Send a digitally signed or encrypted message for Mac

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See Also

Fixes or workarounds for recent issues in Outlook for Mac