Senior Microsoft System Administrator (Active Directory, Exchange, M365)

About the role

We are looking for a senior Microsoft System Administrator to design, implement, and support our enterprise Microsoft infrastructure. The role covers Active Directory, Exchange, Microsoft 365, identity services and related virtualization and endpoint management. You will own the stability, security and performance of critical Microsoft services across the organization.

Key responsibilities

• Design, deploy and maintain Active Directory, Group Policy, DNS, DHCP, domain controllers and fail‑over clustering.
• Administer Windows Server environments on physical and virtual platforms, monitor health, capacity and apply patches.
• Configure and manage ADFS, Azure AD Connect, Microsoft Entra ID, RBAC and privileged access solutions.
• Operate Exchange Server, Database Availability Groups, mail flow, connectors and hybrid deployments; manage Microsoft 365 licensing and services.
• Maintain PKI and Certificate Authority services, issue and renew certificates, and document standards.
• Collaborate with cybersecurity, application and infrastructure teams to ensure compliance and service continuity.

Required profile

• Extensive hands‑on experience with Microsoft infrastructure in large enterprises.
• Strong knowledge of identity and access management, including ADFS, Azure AD and privileged access.
• Proven ability to troubleshoot complex server and messaging issues.
• Excellent documentation and cross‑functional collaboration skills.

Required skills

• Active Directory, Group Policy, DNS, DHCP, fail‑over clustering
• Windows Server (physical & virtual)
• Azure AD Connect, ADFS, Microsoft Entra ID, RBAC, Privileged Access Management
• Exchange Server, Database Availability Groups, mail flow, hybrid configuration
• Microsoft 365 administration and licensing
• PKI, Certificate Authority, certificate lifecycle management