Turn off contact export
Supported on: At least Windows Server 2008 R2 or Windows 7
Registry
HKCU
software\policies\microsoft\office\16.0\outlook Value name: disableexportingcontact
Enabled: disableexportingcontact = 1
Disabled: disableexportingcontact = 0
Description
This policy setting controls the ability of users to export contact information from the address book. If you enable this policy setting, the "Add to Contacts" menu is not configurable in the address book. If you disable or do not configure this policy setting, the "Add to Contacts" menu is configurable.