Configure

Virus Protection, Spam Protection, Anti-Phishing, Link Protection, Typo squatting Detection, DoS Attack Protection, Outbound Email Encryption for sensitive data, Outbound Filtering DLP (Data Loss Prevention), Email Continuity – Auto fail-over of email services if 365 goes offline & Self-Managed. 30-Day searchable Archive.
(working mailbox is required) [can integrate with M365 or MX-Relayed ]
Self-managed, Bill yearly.