Defender Administrator

Job Title: Defender Administrator Location: Gloucester / Warrington (Hybrid, On-Site Work Required) Rate: £425 per day (Inside IR35) Start Date: 30th September 2025 Duration: TBC Role Overview: We are looking for a skilled Defender Administrator to lead the migration from Symantec/McAfee antivirus solutions to Microsoft Defender (ATP) across Windows and Linux servers in a highly regulated environment.

If you would like to know a bit more about this opportunity, or are considering applying, then please read the following job information.

Key Responsibilities: Migrate servers from legacy AV to Microsoft Defender ATP.

Validate and implement AV exclusion policies.

Design migration strategies for secure environments.

Create and manage AAD device groups for policy deployment.

Conduct connectivity testing, build Defender installation packages, and manage distribution.

Remove legacy AV and ensure robust endpoint security.

Provide end-to-end Defender support, including policy creation, monitoring, and reporting.

Participate in out-of-hours and on-call support as required.

Skills & Experience: 4 years' experience onboarding Windows and Linux servers to Microsoft Defender.

Proven AV migration experience in complex environments.

Strong knowledge of Microsoft security tools (Defender for Endpoint, O365, Identity, Cloud App Security).

Expertise in EDR, Threat & Vulnerability Management, Attack Surface Reduction, and Auto Remediation.

Experience with Symantec Endpoint Protection and McAfee.

Strong Windows (7/8/10, Server 2008-2016) and RHEL Linux knowledge.

Deployment experience via GPO, SCCM, or Intune.

Eligible for UK Security Clearance (5 years UK residency required).

If you are interested please email your CV to for immediate considerationd02fcfcb-6df4-40ee-95cf-3eb059ce3173