Turn off Hierarchical Address Book

Category

User Configuration > Administrative Templates > Microsoft Outlook 2016 > Account Settings > Exchange

Scope

User

Registry Key

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

Description

This policy setting turns off the Hierarchical Address Book (HAB). If you enable this policy setting, the HAB will be turned off. If you disable or do not configure this policy setting, the HAB will be displayed.