Microsoft 365: SMTP onboarding to App Role Based Access Control

We're simplifying how organizations grant applications permission to send email on behalf of mailboxes. Today, customers must manually assign permissions to each individual mailbox using PowerShell, which is time-consuming and inefficient. With this new capability, admins can assign the SMTP.SendAsApp role to an app through App Role-Based Access Control (RBAC), enabling group-based or scoped access to mailboxes. This eliminates the need for per-mailbox configuration and streamlines onboarding for SMTP clients using OAuth. It’s a scalable, secure, and modern approach to managing mailbox access for applications.