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# 3rd Line Support Engineer (M365 & Messaging)

- **Company:** Searchability
- **Location:** Manchester, UK
- **Experience:** Experienced
- **Salary:** £126,100.0
- **Contract:** Temporary contract
- **Skills:** Microsoft Windows, Cyber Security, Information Leak Prevention, Data Security, Email Filtering, Simple Mail Transfer Protocols, Microsoft Office, Phishing, Secure Messaging, Microsoft SharePoint, Website Architecture, Software Troubleshooting
- **Published:** August 30, 2026
- **Apply:** https://www.collegerecruiter.com/job/2815457990-3rd-line-support-engineer-m365--messaging

## About the Role

* Proven experience providing 3rd Line Support within enterprise Microsoft 365 environments
 * Expert knowledge of Exchange Online and Exchange Hybrid
 * Strong experience supporting complex messaging environments
 * Hands-on experience with Proofpoint, Clearswift, Egress or PGP
 * Strong knowledge of Exchange Online Protection (EOP)
 * Experience with Microsoft Defender for Office 365
 * Experience troubleshooting email delivery, mail flow and SMTP routing
 * Knowledge of secure email encryption, DLP and information protection
 * Experience administering Microsoft 365, including Exchange Online, SharePoint Online, Teams and OneDrive
 * Knowledge of Microsoft 365 security, compliance and governance
 * Experience supporting SharePoint Online permissions, document libraries and site architecture
 * Strong troubleshooting, analytical and documentation skills

## Description

You'll act as the technical escalation point for complex incidents, problems and service requests, supporting Exchange mail flow, hybrid messaging environments, secure email encryption and Microsoft 365 collaboration services. Working closely with Infrastructure, Security Operations and Service Management teams, you'll help ensure the availability, security and compliance of a large-scale Microsoft 365 environment., * Provide expert 3rd Line support across Microsoft 365 messaging and collaboration services

 * Troubleshoot complex Exchange Online and Exchange Hybrid issues
 * Investigate and resolve mail flow, SMTP routing and email delivery problems
 * Support secure email encryption technologies including Egress and PGP
 * Administer Proofpoint and Clearswift email security platforms
 * Configure transport rules and mail routing policies
 * Manage anti-spam, anti-phishing and Exchange Online Protection policies
 * Support Microsoft Defender for Office 365 security capabilities
 * Investigate phishing campaigns, spoofing attempts and email security incidents
 * Manage Data Loss Prevention (DLP) policies and secure information sharing
 * Support SharePoint Online administration including permissions and content management
 * Collaborate with Security Operations and Infrastructure teams to maintain secure messaging services
 * Produce technical documentation and support knowledge transfer activities


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