Active X One-Off forms must only be enabled to load with Outlook Controls.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-223352O365-OU-000007SV-223352r961092_ruleCCI-001170medium
Description
By default, third-party ActiveX controls are not allowed to run in one-off forms in Outlook. You can change this behavior so that Safe Controls (Microsoft Forms 2.0 controls and the Outlook Recipient and Body controls) are allowed in one-off forms, or so that all ActiveX controls are allowed to run.
STIGDate
Microsoft Office 365 ProPlus Security Technical Implementation Guide2025-03-05

Details

Check Text (C-223352r961092_chk)

Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Security >> Allow Active X One Off Forms is set to "Enabled" "Load only Outlook Controls". Use the Windows Registry to navigate to the following key: HKCU\software\policies\microsoft\office\16.0\outlook\security If the value for allowactivexoneoffforms is REG_DWORD = 0, this is not a finding.

Fix Text (F-25013r442276_fix)

Set the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Security >> Allow Active X One Off Forms to "Enabled" "Load only Outlook Controls".