Disable Mail Tips
Supported on: At least Windows Server 2008 R2 or Windows 7
Registry
HKCU
software\policies\microsoft\office\16.0\outlook\options\mail Value name: disablemailtips
Enabled: disablemailtips = 1
Disabled: disablemailtips = 0
Description
This policy setting determines whether users can view Mail Tips. If you enable this policy setting, Mail Tips do not appear in Outlook. If you disable or do not configure this policy, Mail Tips appear in Outlook.