Enable an Archive Mailbox

  • Article

Applies to: Office 365 for enterprises

You can create an archive mailbox for a user's primary cloud-based mailbox. Users can use the archive mailbox, also called a personal archive, to store historical messaging data by moving or copying messages from their primary mailbox to their archive mailbox. The archived messages reside in the cloud, and users can access it from any computer using Microsoft Outlook 2010 or Outlook Web App.

This topic explains the following:

  • Why use archive mailboxes?
  • Size of the archive mailbox
  • Enable the archive mailbox
  • Disable the archive mailbox
  • Enable archive mailboxes for all users in your organization by using Windows PowerShell
  • Next steps

Why use archive mailboxes?

Archive mailboxes can help you implement and manage your organization's archiving strategy. Users typically use personal store (.pst) files to store historical messaging data on their local computer, network shares, or a USB drive. An archive strategy that relies on .pst files has many disadvantages:

  • The proliferation of .pst files that are stored in different locations
  • Limited access by administrators to .pst files that reside on a local computer or removable media
  • Risk of data theft because .pst files can reside on portable devices such as laptops, portable hard drives, and USB drives
  • Difficulty searching .pst files for data relevant to legal cases

These issues with .pst files make it hard for an organization to manage archived messages. Archive mailboxes help mitigate these issues in the following ways:

  • They provide users with a single, unified archive for managing their messaging data
  • They allow users to:
    • Access their archive messages from any computer, by using Outlook Web App.
    • Easily copy or move messages between their primary and archive mailboxes.
    • Search their entire mailbox in Outlook 2010 or Outlook Web App. Because the archive mailbox isn't cached locally on the user's computer, search results include items found in the users' archive mailbox.
  • They help address compliance needs in the following ways:
    • Archive mailboxes are searched when you perform a multi-mailbox search.
    • When litigation hold is enabled, a litigation hold applies to a user's primary and archive mailbox.
    • An archive mailbox contains its own Recoverable Items folder and is subject to the same Recoverable Items folder quotas as the primary mailbox. To learn more about recoverable items, see Recover Deleted E-Mail Messages in Exchange Online.
    • When an archive mailbox is enabled, retention policy tags with a retention action of Move to Archive are applied. For a list of default retention tags that are configured with a Move to Archive action, see Retention settings in Exchange Online.
      Note   In Exchange Online, by default, messages are automatically moved to the archive mailbox after two years. This applies to all items in a mailbox that don't have a retention tag already applied.

Size of the archive mailbox

The default quota size for an archive mailbox depends on the type of user license assigned to the mailbox.

  • Exchange Online (Plan 1)   Users receive a combined total size of 25 GB for their primary mailbox and archive mailbox. Therefore, the size of the user’s archive mailbox can’t exceed 25 GB.
  • Exchange Online (Plan 2)   Users receive unlimited storage in their archive mailbox. However, a default quota of 100 GB is set on the archive mailbox. In the unlikely event that a user reaches this quota, contact Office 365 support to request more storage space for the archive mailbox.

Note   Administrators in a cloud-based organization can’t change the quota size for an archive mailbox.

Enable the archive mailbox

  1. Select Manage My Organization > Users & Groups > Mailboxes.
  2. Select the mailbox you want to enable the archive mailbox for and click Details.
  3. Under Mailbox Features, select Archive and click Enable.
  4. In the Archive Mailbox window, accept the default archive name (Archive Mailbox - <display name>) or type a new name.
  5. Click Save. Note that the status for Archive is now Enabled.

After you save the change, the archive icon Archive Mailboxes is displayed in the mailbox list for the user's mailbox to indicate the archive mailbox is enabled.

Note   When you assign Full Access permissions to a mailbox, the delegate to which you assign the permissions can also access the corresponding archive mailbox. However, you can’t assign permissions directly to an archive mailbox.

Disable the archive mailbox

Caution   When you disable an archive mailbox, the contents of the archive are permanently removed. The archive won't be accessible by the user and you can't reconnect the archive mailbox to the corresponding primary mailbox.

  1. Select Manage My Organization > Users & Groups > Mailboxes.
  2. Select the mailbox to disable the archive mailbox for and click Details.
  3. Under Mailbox Features, select Archive and click Disable.
  4. In the warning window, click Yes to disable the archive. At this point, disabling the archive mailbox is pending. You have to save this change for the archive to be disabled.
  5. Click Save to complete the process.

If you enable the archive mailbox after disabling it, a new archive mailbox is created, and it won't contain the contents from the previous archive.

Enable archive mailboxes for all users in your organization by using Windows PowerShell

Before you begin   To learn how to install and configure Windows PowerShell and connect to the service, see Use Windows PowerShell in Exchange Online.

To enable an archive mailbox for all users in your organization, run the following command:

Get-Mailbox -ResultSize unlimited -Filter {(RecipientTypeDetails -eq 'UserMailbox')} | Enable-Mailbox -Archive

When you run this command, the archive mailbox name is set to “Online Archive – <display name>” by default. For example, the archive mailbox name for Chris Cannon is “Online Archive – Chris Cannon.” The archive mailbox is displayed in the folder list in the Navigation Pane in Outlook or Outlook Web App.

You can also configure a different archive name when you use Windows PowerShell to enable archive mailboxes. For example, to name archive mailboxes “Personal Archive - <display name>” when you enable archive mailboxes for all users in your organization, run the following commands:

$users = Get-Mailbox -ResultSize unlimited -Filter {(RecipientTypeDetails -eq 'UserMailbox')}

ForEach ($a in $users) {$a.ArchiveName.Add("Personal Archive - $a")}

$users | %{Enable-Mailbox $_.Identity -Archive -ArchiveName $_.ArchiveName}

Next steps

After you enable an archive mailbox, you can change its name. How? See Change the Name of an Archive Mailbox.