Policy

Always use TNEF formatting in S/MIME messages

This policy setting allows you to specify the formatting when sending S/MIME messages. If you enable this policy setting, Outlook always uses TNEF formatting when sending S/MIME messages. If you disable or do not configure this policy setting, Outlook uses the format specified by the user when sending e-mail messages, including when sending S/MIME messages.

Policy
PackMicrosoft Office
CategoryMicrosoft Outlook 2016 / Security / Cryptography
Policy ID27d314b74ca1
Internal nameL_OutlookTNEFinSMIMEmessages

Registry

Copy registry mappings

HKCU\software\policies\microsoft\office\16.0\outlook\security\forcetnef (enabled) = 1
HKCU\software\policies\microsoft\office\16.0\outlook\security\forcetnef (disabled) = 0

Policy notes

This policy setting allows you to specify the formatting when sending S/MIME messages. If you enable this policy setting, Outlook always uses TNEF formatting when sending S/MIME messages. If you disable or do not configure this policy setting, Outlook uses the format specified by the user when sending e-mail messages, including when sending S/MIME messages.

Related policies

Check for the user's private key when the user sends an encrypted email that includes the user as a recipientDo not check e-mail address against address of certificates being usedDo not display 'Publish to GAL' buttonDo not provide Continue option on Encryption warning dialog boxesEnable Cryptography IconsEnable Retrieval of Remote Certificate Authority InformationEncrypt all e-mail messages