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Using Archive Mailboxes in Office 365

Archive mailboxes are now available in Office 365. Archive mailboxes act as extension of a user's mailbox. Once enabled, an archive mailbox will automatically be added to a user's view in Outlook or Outlook Web App. While a user's mailbox is limited to 100GB, items in the archive mailbox do not count against the 100GB limit of a user's primary mailbox. Refer to the information below for more information about Archive mailboxes.

Request an Archive Mailbox

  • Users or administrators can request an Archive Mailbox be enabled for a mailbox by sending a request to

Using an Archive Mailbox

  • Users can use Microsoft Outlook or the Office 365 Portal to view and manage their archive mailbox. An archive mailbox appears as an additional mailbox in Outlook or Outlook Web App at the same "level" as the user's primary mailbox.
  • Personal retention policies can be applied by a user to automatically move items to the user's archive mailbox after the specified amount of time. Note that Personal retention policies cannot be applied against system folders including the Inbox, Sent Items, and Deleted Items folders.
  • When an archive mailbox is enabled for a user, auto-archive options (ex: move to an archive .PST after 6 months) are no longer available in Outlook. Users can use archive policy settings to automatically move items from individual folders to the archive mailbox by viewing the properties of a given folder in Outlook, accessing the "Policy" tab, and selecting an option under "Online Archive."
  • Users can move or copy (ex: "drag and drop") items between their primary mailbox or a .PST and their archive mailbox.

Limitations of Archive Mailboxes

  • Archive Mailboxes have a quota of 100GB, which makes the total quota for a user mailbox 200GB (100GB quota for primary mailbox + 100GB for archive mailbox)
  • Archive Mailboxes cannot be viewed or managed using mobile devices.
  • Users cannot use Inbox rules in Outlook and Outlook Web App to place email directly in an archive mailbox. Users can use rules to move or copy items to a personal folder (i.e. a folder created by the user in their O365 mailbox) and use Personal retention policies applied to the folder to move items to their archive mailbox after a set amount of time.
  • A single archive mailbox cannot be shared between users. An archive mailbox is an extension of a user's mailbox. If a user with an archive mailbox enabled were to leave the university, both the user's primary and archive mailbox would be removed from the system per normal eID de-provisioning processes.