Join Optum, a global leader in health optimization, and contribute to improving health outcomes for millions. As a Senior Microsoft 365 / Exchange Online Engineer, you will own and manage our Microsoft 365 tenant services, ensuring reliable operations and secure configurations for our extended workforce.

This role involves safeguarding our Microsoft 365 and Entra ID environments, supporting approximately 10,000 external agents. You will play a key part in aligning tenant operations, identity controls, and email protection with enterprise policies, including supporting a significant migration from Google Workspace to Microsoft 365.

Key responsibilities include engineering and administering Microsoft 365 tenant services, with a focus on Exchange Online and messaging operations. You will manage mailboxes, recipients, groups, and transport configurations.

This position also involves planning and executing mailbox onboarding, migration waves, and coexistence activities. You will monitor service health, manage licenses, plan capacity, and generate operational reports. Developing PowerShell automation for routine tasks and troubleshooting service incidents, mail delivery issues, and configuration defects are also core duties. Adherence to formal change management processes via ServiceNow is essential.

We are seeking candidates with hands-on experience in administering Microsoft 365 and Exchange Online within large, complex environments. Proven experience with migration execution, production cutovers, and hypercare support is required.

Demonstrated expertise in recipient management, transport configuration, mail flow, and service troubleshooting is essential. A solid understanding of identity dependencies, security controls, DNS, SMTP, and enterprise monitoring is necessary. Proficiency in Exchange Online PowerShell and Microsoft 365 administrative tools is a must. Strong written communication and technical documentation skills are also required.