Hi @Lucas Vorms ,
You can disable the Autodiscover query to Office365 using the registry key.
HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\AutoDiscover
Create a DWORD value for ExcludeExplicitO365Endpoint and change the value to "1":
RegKey: ExcludeExplicitO365Endpoint
Value: 1
You can create GPO to create this registry and push it to the client machines
https://thesolving.com/server-room/how-to-deploy-a-registry-key-via-group-policy/
Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.
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