Always use Rich Text formatting in S/MIME messages

By default, Outlook uses the format specified by the user when sending e-mail messages, including when sending S/MIME messages. By enabling this setting, you can change this behavior so that Outlook always uses Rich Text formatting when sending S/MIME messages.

Supported on: At least Windows Vista
Registry HiveHKEY_CURRENT_USER
Registry PathSoftware\Policies\Microsoft\Office\12.0\Outlook\Security
Value NameForceTNEF
Value TypeREG_DWORD
Enabled Value1
Disabled Value0

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