Defender Administrator in Gloucester

Overview

Job Title: Defender Administrator (Contract)

Location: Gloucester or Warrington (Hybrid on-site)

Rate: £370/Day Inside IR35

Clearance: Must hold or be eligible for Security Clearance (minimum 5 years UK residency)

About the Role

We are recruiting an experienced Defender Administrator to support a large-scale migration programme, transitioning Windows and Linux servers from legacy antivirus solutions (Symantec/McAfee) to Microsoft Defender (ATP). You will play a key role in designing and implementing migration approaches within a complex and sensitive environment.

Key Responsibilities

• Migrate Windows and Linux servers to Microsoft Defender (ATP).
• Validate existing antivirus exclusion policies across the estate.
• Implement MDE policies and create AAD device groups.
• Develop migration approaches suitable for complex and sensitive infrastructures.
• Perform network connectivity testing and ensure readiness for deployment.
• Create and distribute Defender installation packages.
• Lead discussions with the image management team regarding MDE images for auto-scaling.
• Remove legacy AV solutions from servers.
• Provide end-to-end support for Microsoft Defender.

Required Skills & Experience

• 4+ years\\\’ experience onboarding Windows and Linux servers to Microsoft Defender.
• Strong experience migrating from Symantec and McAfee.
• Expertise in AV exclusion management.
• Solid knowledge of Microsoft Defender for Server, O365, Identity, and Microsoft 365 Defender.
• Understanding of EDR, TVM, ASR, AIR and threat remediation.
• Proficiency with Windows OS (Client & Server) and Linux (RHEL).
• Experience deploying ATP packages via GPO, SCCM or Intune.
• Strong investigative and analytical problem-solving skills.
• Ability to document policies, deployment approaches and processes.
• Excellent communication and stakeholder-management skills.

Additional Requirements

• Willingness to work shifts, out-of-hours, and participate in an on-call rota when required.
• Strong relationship-building skills with both onsite and offshore teams.
• Ability to learn quickly and adapt to evolving technical environments.

If you have the required technical expertise and enjoy working in secure, complex environments, we\’d love to hear from you.