User Configuration > Administrative Templates > Microsoft Outlook 2016 > Account Settings > Exchange
User
HKCU\software\policies\microsoft\office\16.0\outlook\autodiscover
This policy setting controls whether a user’s Active Directory Primary SMTP address is automatically used when any new profile is created. If you enable this policy setting, when a user creates any new profile, the user’s Active Directory Primary SMTP address is used for the profile. The user can only enter a profile name. The wizard used to configure specific profile settings is not shown to the user as the profile is created. Note: If you want only the first new profile to use the Active Directory Primary SMTP address, and allow the user to specify a different SMTP address when creating other profiles, then use the “Automatically configure profile based on Active Directory Primary SMTP address (one-time only)” policy setting instead. If you disable or don’t configure this policy setting, when a user creates a new profile, the wizard used to configure specific profile settings is shown to the user and the user can specify any SMTP address as the profile is created.