Hello Atifah,Microsoft Office 365 connector supports Modern Authentication (Certificate-Based Authentication) in Exchange Online, starting with version 14.4.
Please see this document:https://techdocs.broadcom.com/us/en/symantec-security-software/identity-security/identity-management-and-governance-connectors/1-0/connectors/microsoft-connectors/microsoft-office-365.htmlRegards,Dmytry