Frequently asked questions about Microsoft 365 Backup (Preview)


This feature is currently in preview and subject to change.

Has Microsoft's stance on shared responsibility of data protection changed?

No, we still have the same point of view, but are now offering additional tools to help organizations achieve those goals and responsibilities.

Why don’t Disaster Recovery copies suffice for my backup?

Disaster Recovery (DR) is the ability to recover from a situation in which the primary data center is unable to continue to operate. A DR copy with Microsoft 365 maintains the current state of content, not any historical versions from prior points in time. Microsoft 365 Backup provides additional benefit by giving you a way to restore data back to a healthy state in the past with fast RTO to with short RPO intervals.

Why don’t versions already solve this point in time restore problem?

Versions give individual users a way to restore files or sites to prior points in time, but that kind of recovery method doesn't scale well for mass ransomware attacks where an admin needs to orchestrate the recovery. Versions might also be exhausted depending on the version limit set by the admin.

Legal holds retain data, but that feature is optimized for export (for example, via eDiscovery), not for mass restore. Microsoft 365 Backup gives the right enhanced restore tooling for ransomware and accidental/malicious deletions at scale, plus optimized performance for those scenarios.

What mailbox changes are “backed up”?

Mailbox backup enables the recovery of copies of mailbox item “versions.” Versions are created by two types of actions:

  • Modifications
  • Deletions

Example events that are versions and recoverable via backup:

User action

  • Edit a received email using ‘edit message’ via OL
  • Edit a Note (not draft)
  • Remove an attachment from an email
  • Edit an attachment to an email
  • Edit a contact (not draft)
  • Modify body of a calendar invite
  • Update time of a calendar invite
  • Edit a task (not draft)
  • Delete note from deleted items
  • Delete email from deleted items
  • Purge items from single item retention
  • Delete a folder with items in it

Example events that aren't versioned or recoverable via backup:

User action

  • Edit an email item in the drafts folder
  • Update a flag on a received email
  • Set ‘Do Not Forward’ on a received email
  • Set a received message to highly important

What is the service recovery point objective?

The recovery point objective (RPO) is the maximum amount of time between the most recent backup and a data destruction event. Stated another way, it’s the amount data lost due to a data destruction event not recoverable via the backups. In the case of Microsoft 365 Backup, the RPOs are:

For OneDrive and SharePoint, the RPO for the first two weeks is 15 minutes, then one week beyond that. This means for the first two weeks, the most amount of data that can be lost due to a data destruction event is roughly 10 minute’s worth of the most recent data. Likewise, after two weeks, the most amount of data that can be lost is a week’s worth of data.

For Exchange Online, the RPO is 10 minutes, meaning the most amount of data that can be lost due to a data destruction event is roughly 10 minutes’s worth of data.

Let's start with what it doesn't mean: We are not taking snapshots every 10 minutes.

Backup frequency of 10 minutes (if the item is modified) means that changes to the item will be saved as a version once every 10 minutes, no matter how many changes are made in that 10-minute interval. For example, if a ransomware attack encrypts the email item every minute, will we take six copies in an hour.