You need to log in to create posts and topics.

Import MBOX to Microsoft 365 mailbox in 2026

If you're looking to import MBOX files into Office 365 without compromising data integrity, it is tough to implement.

Many users are looking to migrate from MBOX-based email clients, such as Thunderbird, Apple Mail, etc.

After trying manual methods and a few tools, I found that maintaining data integrity during MBOX to Office 365 migration requires three key things:

  • Preserving original folder hierarchy
  • Maintaining email metadata (To, From, CC, timestamps, attachments)
  • Avoiding duplicates and corruption

Using the manual method can do the migration, but it requires technical expertise, and the chances of data loss/corruption are very high. Keeping this in mind, we use a third-party tool called Shoviv MBOX to Office 365 Migration that makes it more productive and efficient.

Key highlights:

  • It is capable of migrating directly from MBOX to Office 365
  • The tool can preserve folder structure and email properties
  • It supports large mailbox migrations without corruption
  • Incremental export to prevent duplicates
  • The software has the facility of bulk migration
  • Detailed logs for audit and verification

Best practices to avoid data loss:

  1. Always take a backup of the original MBOX files.
  2. Run a pilot migration before full deployment.
  3. Validate folder mapping and permissions.
  4. Use incremental migration for staged rollouts.

In my experience, using a specialized tool like Shoviv significantly reduces migration risks and ensures the data remains intact and accessible post-migration.