How to Recover a Deleted Mailbox in Exchange

In Exchange, if you delete a mailbox, it is disconnected for a default period of 30 days (the mailbox retention period), and you can reconnect it at any point during that time. Deleting a mailbox does not mean that it is permanently deleted (or purged) from the information store database right away, only that it is flagged for deletion. At the end of the mailbox retention period, the mailbox is permanently deleted from the database. You can also permanently delete the mailbox by choosing to purge it at any time.

This also means that if you mistakenly delete a mail-enabled user account, you can recreate that user object, and then reconnect that mailbox during the mailbox retention period.

Configure the deleted mailbox retention period at the mailbox store object level.

To Delete a Mailbox in Exchange

1. Right-click the user in Active Directory Users and Computers.
2. Click Exchange Tasks.
3. Click Next on the Welcome page of the Exchange Task Wizard.
4. Click Delete Mailbox.
5. Click Next, click Next, and then click Finish.

The mailbox is now flagged for deletion and will be permanently deleted at the end of the mailbox retention period unless you recover it.

To Reconnect (or Recover) a Deleted Mailbox

1. In Exchange System Manager, locate the mailbox store that contains the disconnected mailbox.
2. Click the Mailboxes object under the mailbox store.
3. If the mailbox is not already marked as disconnected (the mailbox icon appears with a red X), right-click the Mailboxes object, and then click Cleanup Agent.
4. Right-click the disconnected mailbox, click Reconnect, and then select the appropriate user from the dialog box that appears.
5. Click OK.

Note Only one user may be connected to a mailbox because all globally unique identifiers (GUIDs) are required to be unique across an entire forest.

To Reconnect a Deleted Mailbox to a New User Object

1. In Active Directory Users and Computers, create a new user object. When you create the new user object, click to clear the Create an Exchange Mailbox check box.
   
   You will connect this user account to an already existing mailbox.
2. Follow steps 1 through 4 in the preceding "To Reconnect (or Recover) a Deleted Mailbox" section.

To Configure the Mailbox Retention Period

1. Right-click the mailbox store, and then click Properties.
2. On the Limits tab, change the Keep deleted mailboxes for (days) default setting of 30 to the number of days you want.
3. Click OK.