Does Microsoft back up your Microsoft 365 data? Not the way you think

The shared responsibility model

Microsoft runs a highly resilient service. If one of its data centres has a problem, your email keeps working. But Microsoft’s own terms make clear that protecting your data from deletion, corruption or misuse is your responsibility, not theirs. That’s known as the shared responsibility model.

Where the gaps are

• Accidental deletion. Deleted emails and files sit in recycle bins for a limited time, then they’re gone for good.
• Ransomware. If files synced through OneDrive are encrypted, the damaged versions sync to the cloud too.
• Departing staff. When a licence is removed, that person’s mailbox and OneDrive are deleted after a short grace period.
• Malicious changes. A disgruntled employee or a hijacked account can delete or overwrite large amounts of data.
• Legal and regulatory needs. You may need to produce records from years ago.

What proper backup looks like

1. A separate copy of email, OneDrive, SharePoint and Teams, stored outside your Microsoft 365 tenant.
2. Automatic, frequent backups, at least daily.
3. Long retention, measured in years rather than weeks.
4. Fast, granular restores of a single email, a folder or a whole mailbox.
5. Regular test restores so you know it works.

Where should backups live?

For Cayman businesses there’s a strong case for keeping backups on island. It keeps data within Cayman’s jurisdiction, which simplifies data protection questions, and gives you a copy that doesn’t depend on overseas links if a storm affects connectivity.

How CNS can help

Every CNS managed IT plan includes nightly backup of Microsoft 365, or Google Workspace on Premium and Complete, stored in a hurricane-rated data centre in Cayman and kept for three years. Server and PC backup with disaster recovery is available on top.