3rd Line Support Engineer, MSP, M365, Azure, AVD, Security

McGregor Boyall; Greater London; On-site; GBP 65,000 - 80,000; Full time

Job summary

McGregor Boyall is seeking a 3rd Line Support Engineer for a managed services MSP. You will act as a senior technical authority, handling escalations across Microsoft 365, Azure, AVD, and security, and own proactive health checks and audits.

You’ll mentor 1st/2nd line engineers, lead root-cause analyses, and contribute to service improvement initiatives, while engaging with customers remotely or on-site to translate complex technical issues into clear actions.

Qualifications

• Senior Engineer or 3rd Line Engineer in a Managed Services environment.
• Microsoft 365, Azure, Windows Server, Active Directory experience.
• DNS, DHCP, TCP/IP and VPN knowledge and security principles.

Responsibilities

• Act as the primary escalation point for complex and high-impact incidents.
• Lead Problem Management and Major Incident investigations with RCA.
• Resolve advanced incidents and requests across infrastructure, cloud and Microsoft platforms.
• Engage senior technical colleagues, project teams, vendors and partners as required.
• Maintain detailed ticket notes, RCA docs and remediation plans.
• Review and approve technical changes and change control submissions.

Skills

Senior Engineer

Microsoft 365

Azure

Windows Server

Active Directory

Entra ID

Intune

Networking fundamentals

ITSM

Fluent English

Job description

3rd Line Support Engineer, MSP, M365, Azure, AVD, Security

Reporting to the Service Desk Manager, the 3rd Line Support Engineer is a senior technical specialist acting as the final escalation point for complex incidents, problems, and major incidents. You will engage directly with customers as a trusted technical authority and take ownership of proactive managed technical services, including regular audits, health checks, and assessments.

This is a role for an experienced engineer who thinks independently, takes ownership, and can balance deep technical troubleshooting with structured, proactive service delivery.

Success in this Role Will Be Demonstrated By:

• Ensuring escalations are resolved efficiently and correctly, with fewer repeat incidents.
• Helping develop junior engineers to become more capable, confident, and effective professionals.
• Effectively delivering audits and health checks that are valued, repeatable, and impactful.
• Identifying and addressing technical risks proactively.

Key Responsibilities

Escalation Support & Technical Leadership

• Act as the primary escalation point for complex and high-impact incidents across managed services.
• Lead Problem Management and Major Incident investigations, including root cause analysis (RCA) and preventative recommendations.
• Resolve advanced incidents, problems, and non-standard requests across infrastructure, cloud, and Microsoft platforms.
• Engage senior technical colleagues, project teams, vendors, and third-party partners when required.
• Maintain detailed ticket notes, RCA documentation, and remediation plans.
• Act as a peer reviewer for technical changes and change control submissions, ensuring quality and risk awareness.
• Continuously improve service quality, resilience, and security through analysis and recommendations.

Managed Technical Services Ownership

• Own and deliver repeatable, high-quality managed technical services, including:
  • Monthly or quarterly technical health checks
  • Technical baseline reviews
  • Microsoft 365, Azure, endpoint and infrastructure audits
  • Configuration and best-practice assessments
• Produce professional technical reports with practical recommendations.
• Identify service risks, gaps, and improvement opportunities before they become incidents.
• Contribute to Continual Service Improvement (CSI) initiatives and service roadmaps.
• Work closely with Service Delivery and Account Management teams to ensure recommendations translate into measurable improvements.

Client Engagement & Technical Authority

• Act as a technical escalation point for customers during critical incidents and complex investigations.
• Attend client meetings remotely or on-site where technical expertise is required.
• Support Account Managers and Service Delivery Managers with:
  • Technical service reviews
  • Proposal validation and solution assurance
  • Service transition and early-life support
• Communicate complex technical issues clearly to both technical and non-technical stakeholders.

Technical Mentoring & Knowledge Leadership

• Act as a mentor and role model for 1st and 2nd Line Engineers.
• Coach engineers on troubleshooting techniques and diagnostic thinking.
• Deliver internal knowledge-sharing sessions covering:
  • Recurring issues and lessons learned
  • New technologies and platform changes
  • Best-practice operational approaches
• Help raise the overall technical capability and confidence of the service desk.

Documentation, Standards & Process Improvement

• Create, review and improve:
  • Technical procedures and runbooks
  • Known error records and troubleshooting guides
  • Service and platform documentation
• Ensure documentation remains current as environments evolve.
• Contribute to ongoing improvements in tooling, standards, and operational processes.
• Support project handovers and service transitions to ensure operational readiness.

Qualifications, Skills & Experience

Essential Experience

• Proven experience operating as a Senior Engineer or 3rd Line Engineer within a Managed Services environment.
• Strong experience with Microsoft technologies including:
  • Microsoft 365 (Exchange, Teams, SharePoint, Entra ID, Intune)
  • Windows Server
  • Active Directory
  • Azure (core services, identity, and networking fundamentals)
• Solid understanding of:
  • Endpoint and device management
  • DNS, DHCP, TCP/IP and VPN technologies
  • Security principles and best practices
• Experience working with ITSM platforms and ITIL-aligned processes.
• Fluent spoken English with excellent written communication skills, including technical documentation.

About You

• Professional and calm under pressure.
• Positive and proactive attitude.
• Comfortable owning complex issues through investigation, resolution and prevention.
• Strong problem-solving and analytical skills.
• Confident engaging with customers and stakeholders.
• Passionate about innovation and service improvement.
• Excellent verbal and written communication skills.
• Patient, approachable and supportive of colleagues' development.
• Methodical with strong attention to detail.
• High sense of urgency, accountability and ownership.

3rd Line Support Engineer, MSP, M365, Azure, AVD, Security