Microsoft 365 users occasionally reach the 50GB storage limit that comes with standard licenses. In these instances, Microsoft provides an additional 50GB through the Online Archive feature, effectively doubling your email storage capacity. For businesses requiring more storage, the Microsoft 365 E3 license offers an expansive 100GB mailbox, coupled with an unlimited online archive.

In this guide, we explain how to manage your Microsoft 365 storage and activate the Mailbox Archive feature. This valuable tool not only increases your email storage capacity but also helps to organize and secure important data.

Step-by-Step Guide on Enabling Microsoft 365 Mailbox Archiving

Our process utilizes the default '2-year move to archive' retention tag. Typically, no changes are required here, unless you prefer a different time frame for archiving.

1. Go to Exchange admin center
2. Select mailbox that you want to to use mailbox archiving
3. Take note of mailbox usage, in Robert's case we are at 88.7% used.
   
4. Go to Others tab > Manage mailbox archive
   
5. Enable Mailbox archive status.
6. Choose a Name of the folder in the user's mailbox that contains the archive.

Optionally, if you're looking to speed up the archiving process in Microsoft 365, you can use the PowerShell Exchange module to force the archive to start immediately, bypassing the usual seven-day initiation period. Replace 'MAILBOX_EMAIL_ADDRESS' with the email address of the mailbox you wish to target.

Here's how you can initiate the archiving process:

# Import the Exchange Online Management module
Import-Module ExchangeOnlineManagement

# Connect to Exchange Online
Connect-ExchangeOnline

# Start the archive process
Start-ManagedFolderAssistant 'MAILBOX_EMAIL_ADDRESS'

Confirm the process: After waiting for approximately 5 to 30 minutes, you should be able to see a reduction in the mailbox usage in the Exchange Admin Center. This indicates that the archiving process has started successfully, and your mailbox storage is being efficiently utilized. 🎉