How MRM works in office 365?

Retention policies and retention tagsare part of the MRM technology. Retention policies use retention tags to apply retention settings to e-mail messages and folders. Retention tags define an age limit that specifies how long items are retained, and a retention action that specifies what happens to items that reach the retention age limit. Retention tags are linked to a retention policy, which is then applied to a mailbox.

How MRM works in Exchange Online

Let’s look closer at these components:

  • Retention tagsRetention tags define and apply retention settings to messages and folders in a user’s mailbox. Retention tags specify how long a message is kept and the action taken when the message reaches the specified retention age. When a message reaches its retention age, it’s moved to the user’s archive mailbox or it’s deleted. Retention tags are linked to a retention policy. There are three types of retention tags:
    • Default policy tag (DPT) The settings defined in the DPT apply to all items in a mailbox that don’t have a retention tag already applied. A retention policy can have up to three DPTs linked to it: one DPT with a retention action of Move to Archive, one DTP with a retention action of Delete and Allow Recovery, and one DTP for a specific message class, such as voice mail.
    • Retention policy tags (RPT) RPTs are applied to default folders, such as Inbox, Sent Items, Deleted Items, and Junk Mail. An RPT takes precedence over a DPT.
      Note RPTs don’t support a retention action that moves items to the user’s archive mailbox. The only retention action for RPTs is to delete items.
    • Personal tags Users can use Microsoft Outlook 2010 and Outlook Web App to apply personal tags to custom folders and individual items in their mailbox.
  • Retention policies A retention policy is a group of retention tags that are applied to a mailbox. When a mailbox is created, a default retention policy is applied. In Exchange Online, the default retention policy applied to new mailboxes is named Default MRM Policy. A mailbox can have only one retention policy applied to it.

How are retention policies processed in Office 365?

The Managed Folder Assistant is a process that runs automatically in the Microsoft datacenters to process the retention settings that are applied to a mailbox. The Managed Folder Assistant applies the DPT and RPTs to the mailbox and makes personal tags available in Outlook 2010 and Outlook Web App so that users can apply them to custom folders or specific mailbox items. The Managed Folder Assistant processes the retention of items based on the tag type, retention age, and retention actions defined in each retention tag.

How often does the Managed Folder Assistant run? The Managed Folder Assistant is configured to process all mailboxes in a cloud-based organization in a specific span of time, which is known as a work cycle. In Exchange Online, the work cycle is seven days. This means that the assistant tries to process every mailbox in your cloud-based organization once every seven days.

Because the Managed Folder Assistant is running all the time, you don’t need to do anything to apply retention settings to mailboxes. However, if you need to apply retention settings to a mailbox immediately, you can force the Managed Folder Assistant to process a specific mailbox. See Run the Managed Folder Assistant.

Important MRM doesn’t guarantee retention of every message. For example, a user can delete or remove a message from their mailbox before the message reaches its retention age; MRM isn’t designed to prevent users from deleting their own messages. If your organization requires retention of messages indefinitely, consider using one of these Exchange Online features:

  • Journaling If your organization requires messages to be retained outside a user’s mailbox for long-term storage, use journaling. See Journal Rules.
  • Litigation hold If your organization has to preserve messages to meet e-discovery and retention requirements, you can put user mailboxes on litigation hold. See Put a Mailbox on Litigation Hold.

Also, single item recovery in Exchange Online lets you to recover a deleted e-mail message for up to 14 days after the message is permanently deleted by the user. See Recover Deleted E-mail Messages in Exchange Online.

Retention settings in Office 365

The following table shows the retention tags and their settings, which are available by default in Exchange Online for Microsoft Office 365 and Live@edu. All these tags are linked to the default retention policy that is applied to new mailboxes. That means these settings are applied to all new mailboxes.

When a personal retention tag is linked to the retention policy applied to a user’s mailbox, the retention tag is automatically available to users to apply to their mailbox items.


Tag name Tag type Retention age limit (days) Retention action
Default 2 year move to archive All (DPT)* 730 Move to Archive
Recoverable Items 14 days move to archive Recoverable Items** 14 Move to Archive
Deleted Items Deleted Items folder** 30 Delete and Allow Recovery
Junk Email JunkEmail** 30 Delete and Allow Recovery
Personal 1 year move to archive Personal 365 Move to Archive
Personal 5 year move to archive Personal 1825 Move to Archive
Personal never move to archive*** Personal No age limit Move to Archive
1 Week Delete Personal 7 Delete and Allow Recovery
1 Month Delete Personal 30 Delete and Allow Recovery
6 Month Delete Personal 180 Delete and Allow Recovery
1 Year Delete Personal 365 Delete and Allow Recovery
5 Year Delete Personal 1825 Delete and Allow Recovery
Never Delete*** Personal No age limit Delete and Allow Recovery

* Retention tags with a type of All are DPTs. DPTs apply to items that don’t have another retention tag applied.

** The type for RPTs identifies the default mail folder that the tag applies to.

*** This tag isn’t enabled by default. Items that have this retention tag are either never moved or never deleted.