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# Senior 3rd Line Engineer -MSP

- **Company:** Ashdown Group
- **Location:** London, UK
- **Experience:** Expert
- **Salary:** £55,000.0 - £65,000.0
- **Contract:** Permanent contract
- **Skills:** Microsoft Azure, Windows PowerShell, Azure Active Directory, Office365, Software Troubleshooting, Sonicwall, Firewalls (Computer Science), Microsoft InTune, Fortinet
- **Published:** October 27, 2026
- **Apply:** https://www.totaljobs.com/job/senior-3rd-line-it-support/ashdown-group-job108239564

## About the Role

* Must have 3 rd line experience within an MSP
 * Expert M365 (CA, Intune, hybrid Exchange, ATP)
 * Strong troubleshooting methodology
 * Confident communicator at all levels
 * Full Microsoft Certificates desirable
 * NinjaOne/Datto RMM config
 * Azure infrastructure
 * Firewalls (Fortinet, SonicWall, Draytek)
 * Solid PowerShell skills

## Description

* Act as the top-tier escalation point for complex incidents
 * Lead the rollout + optimisation of NinjaOne RMM (automation, alerting, remediation scripting)
 * Own M365, Intune, Conditional Access, hybrid Exchange, and Azure AD/Entra
 * Mentor engineers in diagnostic methodology
 * Work closely with technical leadership-no non-technical managers blocking decisions