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📖 What is Exchange Online Archiving?

Exchange Online Archiving is a feature that provides users with additional storage space for old emails, moving them out of the primary mailbox. This helps maintain primary mailbox performance and satisfies long-term data retention requirements for legal or business reasons.

🥋 Sensei Says:

"Student, understand the difference between the primary mailbox and the archive; the archive is designed for long-term storage to prevent primary mailbox bloat."

📚 Certification: Microsoft 365 Administrator (MS-102)

🔑 What are the Key Concepts of Exchange Online Archiving?

  • Retention policies and tags automate the movement of emails from the primary mailbox to the archive based on age or specific folder rules.
  • Auto-expanding archiving allows the archive mailbox to grow beyond its initial quota, providing virtually unlimited storage for eligible Microsoft 365 licenses.
  • The archive mailbox is a separate entity from the primary mailbox, reducing the size of the primary data files for improved client performance.
  • Litigation Hold and Retention Policies ensure that archived items are preserved for legal discovery, even if the user attempts to permanently delete them.

🎯 How does Exchange Online Archiving appear on the MS-102 Exam?

You may be asked to resolve a 'mailbox full' warning for a user by enabling an archive mailbox and applying a default MRM retention policy to move old data.

A scenario might describe a legal requirement to retain all corporate communications for seven years, requiring you to configure an archive mailbox and a corresponding retention tag.

Expect questions about a user who has reached the 100GB archive limit, where the correct solution is to enable the auto-expanding archiving feature via PowerShell.

❓ Frequently Asked Questions

What is the difference between the Archive folder and an Online Archive mailbox?

The Archive folder is simply a folder within the primary mailbox and counts toward its quota. The Online Archive is a separate mailbox with its own quota, designed specifically for long-term storage.


Can a user manually move emails to the archive mailbox?

Yes, users can manually drag and drop items into the archive mailbox, but administrators typically use Messaging Records Management (MRM) policies to automate this process based on the age of the items.

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