'Message could not be saved' error sending encrypted email in Outlook 2016 for Mac

Symptoms
In Microsoft Outlook 2016 for Mac, you compose a new encrypted email message addressed to a user in the global address list (GAL). When you click Send, you receive the following error message and the email does not send:

Message could not be saved.



Cause
This issue may occur when the email message recipient's name in the GAL differs from the name on their certificate due to case sensitivity.
Workaround
To work around this issue, manually enter the full email address of the recipient instead of selecting them from the GAL.
SMIME; S/MIME; errmsg;
Properties

Article ID: 3163197 - Last Review: 05/13/2016 19:20:00 - Revision: 1.0

Microsoft Outlook 2016 for Mac, Outlook for Mac for Office 365

  • KB3163197
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