For most UK public sector organisations, the shift to Microsoft 365 has already happened. Mailboxes are in the cloud, Teams is embedded across departments and the organisation has moved firmly into a cloud-first operating model. Yet one element stubbornly remains outside the modern stack: the legacy email archive.
Platforms such as Enterprise Vault, Mimecast, EMC SourceOne, NearPoint and EAS continue to store years – or decades – of historical email. These systems were never designed to coexist permanently with M365, but that’s exactly what ends up happening. The result is a split environment: live mail in M365, and everything else in an ageing, increasingly unsupported archive.
This dual system undermines the benefits that drove the M365 migration in the first place. Staff must search two locations for information, reducing productivity and increasing frustration. FOI and SAR teams face slower turnaround times because evidence may be stored in the legacy archive rather than in M365’s unified eDiscovery tools. Information governance teams also lose the clarity and certainty of consistent retention policies; instead, they inherit a patchwork of legacy rules that no longer reflect organisational policy, or regulatory expectations.
From a technical and financial standpoint, the burden grows. Organisations continue paying for archive licences, storage and maintenance. They absorb the operational risk of running unsupported infrastructure. And they rely on niche expertise that is becoming harder to find.
Migrating the legacy archive into Microsoft 365 brings the organisation back to a single system of record. Search, eDiscovery, retention, auditing and compliance all move into one place: modern, supported and secure. It’s the final step in completing the cloud transformation journey many public sector bodies started years ago, and the longer it’s delayed, the bigger the technical and governance gap becomes.
Ultimate Migrator enables this transition safely, efficiently and at scale, without disruption to staff or services.