SeniorWindowsEngineer

**Join Mizuho as a Senior Windows Engineer!** Th ideal candidate has deep expertise in Microsoft 365, Exchange (Online and On‑Premises), Microsoft Teams and enterprise messaging platforms. In this role, you will be responsible for technical leadership, architecture-level decision making, and delivery of complex messaging and infrastructure initiatives in a large, regulated enterprise environment. Responsibilities: * Serve as a senior technical authority for Microsoft 365 and Exchange, including hybrid Exchange architectures. * Design, implement, and maintain Exchange Online and Exchange On‑Premises environments, including mail flow, transport, migrations, and coexistence. * Lead messaging and directory migration initiatives, including tooling such as Quest On Demand. * Own and integrate email security platforms, including Proofpoint, ensuring reliability, security, and compliance. * Drive end‑to‑end delivery of infrastructure and messaging projects, including upgrades, migrations, and modernization efforts. * Partner with architecture, security, and operations teams to define technical standards and roadmaps. * Author and maintain advanced PowerShell automation for administration, reporting, and operational efficiency. * Act as escalation point for complex M365, Exchange, Active Directory, and Teams issues. * Participate in vendor evaluations, solution design, and capacity planning. * Operate within ITIL-based service management frameworks and support change, incident, and problem processes. * Produce high‑quality technical documentation and provide clear stakeholder communication. * Participate in on-call rotation with senior-level responsibility and ownership. Requirements: * At least 8+ years of experience supporting enterprise Windows and Microsoft messaging platforms (financial services experience preferred). * Advanced hands-on experience with Microsoft 365 and Exchange (Online and On‑Premises) in hybrid environments. * Strong experience designing and supporti