Senior Microsoft 365 Systems Engineer

Job Title: Senior Microsoft 365 Systems Engineer

Location: Bedford, UK

Duration: 3 Months

Hours: 37.5 hours per week

Rate: Dependent on experience

About the Role

We are recruiting a Senior Microsoft 365 Systems Engineer to support, secure, and automate a high-concurrency global workplace environment supporting 150,000+ users worldwide .

Working alongside global infrastructure, security, and networking teams, you will take ownership of enterprise messaging, identity governance, security enforcement, and PowerShell automation across the Microsoft 365 ecosystem and integrated security gateways.

Key Responsibilities

• M365 & Messaging: Administer and optimize Exchange Online, Microsoft Teams, SharePoint Online, OneDrive, and Hybrid Exchange environments at scale.

• Email Security & Domain Protection: Configure, manage, and enforce email security gateways ( Proofpoint ) and email authentication protocols ( DMARC, SPF, and DKIM ).

• Identity & Security Controls: Design and manage Entra ID (Azure AD) , Conditional Access policies, Multi-Factor Authentication (MFA), Single Sign-On (SSO), and Privileged Identity Management (PIM) following Zero Trust principles.

• Automation: Write and maintain advanced PowerShell scripts and Microsoft Graph API solutions to automate administrative tasks and operational workflows.

• Compliance & Governance: Support eDiscovery, retention policies, and data protection using Microsoft Purview and Microsoft Defender for Office 365.

• Hybrid Systems: Support integration points across Windows Server and Linux infrastructure.

Required Qualifications & Experience

• 6+ years of hands-on Microsoft 365 systems engineering experience in large-scale enterprise environments ( 10,000+ users minimum ).

• Deep technical expertise in Exchange Online, Teams, SharePoint, and OneDrive .

• Strong hands-on experience administering Proofpoint email security platforms.

• Proven track record implementing and managing DMARC, SPF, and DKIM domain protection policies.

• Advanced PowerShell scripting capabilities for reporting, automation, and task execution at scale.

• Expertise in Entra ID , Conditional Access, MFA, and PIM (Privileged Identity Management) .

• Experience supporting both Windows Server and Linux environments.

• Excellent troubleshooting, analytical, and technical documentation skills.

How to Apply

If you meet the technical criteria and have experience supporting massive enterprise M365 tenants, please submit your updated CV for immediate consideration.

Randstad Business Support is acting as an Employment Agency in relation to this vacancy.