You must use Microsoft Office365 to add Avaya Oceana® mailbox as a member with the permission to send as a group. Avaya Oceana® uses the mailbox configured to poll new emails. You must configure Avaya Oceana® mailbox to have permissions to send as distribution group on Office365 side.
Exchange Admin Center (EAC) configurations
For information about creating and managing distribution groups in EAC, see Exchange documentation.
For information about how to grant Send As permissions in EAC, see Exchange documentation.
