Enable Retrieval of Remote Certificate Authority Information

Supported on: At least Windows Server 2008 R2 or Windows 7

Registry

HKCU software\policies\microsoft\office\16.0\outlook\security

Value name: enableaiacertextension

Enabled: enableaiacertextension = 1

Disabled: enableaiacertextension = 0

Description

This policy setting controls whether Outlook will use remote certificate authority information in a secure email message to validate that its certificate is trusted. If you enable this setting, you’ll allow the operating system to access remote network locations specified in a certificate for validation. If you disable or don’t configure this setting, retrieval of remote Certificate Authority Information won’t be allowed, and only stored certificates will be used for authentication.