Use the Microsoft 365 admin center to enable or disable SMTP AUTH on specific mailboxes

Use the Microsoft 365 admin center to enable or disable SMTP AUTH on specific mailboxes

1. Open the Microsoft 365 admin center and go to Users > Active users.
2. Select the user, and in the flyout that appears, click Mail.
3. In the Email apps section, click Manage email apps.
4. Verify the Authenticated SMTP setting: unchecked = disabled, checked = enabled.

   When you’re finished, click Save changes.