In CSI on the intranets form, identify the authorized user from the SMTP user account (e.g. eDocs).


In Microsoft 365, under each user's mailbox update their mailbox delegation to grant this user (eDocs) as a "Send As" to the user's account.

Repeat this for all Mailboxes of CSI Users.  This configuration allows "eDocs" to send out event emails as the CSI user.


Reference KB 1406784 - Application Event System Send Email Requirements