Allow Basic Authentication prompts from network proxies

Information

This policy setting controls whether network proxies are allowed to show Basic Authentication prompts. \n By default, all Basic Authentication sign-in prompts are blocked, and the user is shown a message that the sign-in method isnt allowed. \n If you enable this policy setting, then network proxies will be allowed to show Basic Authentication prompts. \n Warning: Allowing Basic Authentication sign-in prompts isnt recommended because its a security risk. \n If you disable or dont configure this policy setting, all Basic Authentication sign-in prompts from network proxes will be blocked, and the user will be shown a message that the sign-in method isnt allowed. \n Note: This policy setting only applies to subscription versions of Office, such as Microsoft 365 Apps for enterprise, and to subscription versions of Project and Visio. \n For more information, see https://go.microsoft.com/fwlink/p/?linkid=2199001.

Solution

Policy Path: Microsoft Office 2016\Security Settings
Policy Setting Name: Allow Basic Authentication prompts from network proxies

See Also

https://techcommunity.microsoft.com/t5/microsoft-security-baselines/security-review-for-m365-apps-for-enterprise-v2312/ba-p/4009591