Information
This policy setting specifies whether replies will be automatically (digitally) signed.
The recommended state for this setting is: Disabled
Disabling this setting and allowing automatic digital signatures will ensure the original sender of a signed message also receives a signed one in return. Breaking the integrity in this trust relationship may cause the other party to disregard the sender's message, causing information and trust to be lost.
Solution
To establish the recommended state via configuration profiles, set the following Settings Catalog path to Disabled :
Microsoft Outlook 2016\Security\Do not automatically sign replies
Impact:
None - this is the default behavior.