Fixing the Microsoft 365 mailbox connection for a UK CRM vendor's multi-tenant product — the missing Outlook permissions on their Azure app, custom-domain and publisher-domain setup, and Microsoft publisher verification through to the verified badge.
A UK software vendor's CRM lets customers connect their Microsoft 365 mailboxes so incoming email can be monitored inside the CRM. The "Connect Microsoft" step kept failing, and customers outside the vendor's own organisation were stopped by an unverified-app warning.
We traced the failure to the Azure side: the app registration only held basic sign-in permissions, not the Outlook mailbox permissions the connection actually asks for. We added those, then took the app through Microsoft's publisher verification — custom domain, publisher domain, linking the right directory to the vendor's Partner Center account — until the app showed the vendor as a verified publisher.
Customers can now connect their Microsoft 365 mailboxes to the CRM through a Microsoft app that carries the vendor's verified-publisher badge, instead of an unknown app with an "unverified" warning. The client rated the work 5.0 and asked to bring further work to us.