Exchange Server 2003 Mailbox Recovery

Recover deleted mailboxes that are tombstoned in the database

If an administrator has deleted a user and with that its mailbox and within 30 days (by default) he discovers that this mailbox should not have been deleted, there is an easy way to reconnect the orphaned mailbox to a new user. The timeline for not deleting an unconnected mailbox from the storage is 30 days by default and can be increased using a private storage system policy.

The administrator can have a look into the private storage of the private storage where he will find all orphaned mailboxes with a red cross. The cleanup agent is the piece of software that regularly scans all mailboxes and checks, if there is a connection between a user object in Active Directory and a mailbox in the private information store. If there is not, it marks the mailbox for deletion. The retention time for the tombstoned mailbox now begins to run. If the cleanup agent has not run yet, you can start him manually by triggering it.

Figure 1: How to manually run the Cleanup Agent

If the administrator has now found the orphaned mailbox he only has to click right on it and choose “Reconnect” to connect it to a new user in Active Directory.

Figure 2: Reconnect a mailbox

With Exchange Server 2003 we have a newly created Mailbox Recovery Center, which makes it easier to reconnect a mailbox. You just have to mount the private store, then you will see only the reconnectable mailboxes and a right click solves your problem.

Figure 3: Reconnect a mailbox using Mailbox Recovery Center

These two methods are easy ways to reconnect an orphaned mailbox that is still available in the storage to a newly created Active Directory User. If the 30 days retention time is not enough, there is an easy way to increase this using system policy. A good feature provided by a private storage system policy is to only delete tombstoned mailbox stores after a backup of the storage was made.

Restoring Mailboxes from the Recovery Databases by Using Exmerge.exe

Exchange Server 2003 provides quite a flexible and easy way to mount storage databases using the new Recovery Storage Group feature. After having started to restore the database from a tape you configure the Recovery Storage Group that can be created by right clicking the server object in Exchange System Manager and choosing to create a Recovery Database Storage Group. Within this group you can now mount your restored database and use the Exmerge utility to move the recovered mailbox data from the Recovery Storage Group to the regular storage group. Using this method, you can recover a whole database or just a single mailbox. Every mailbox that is connected to the Recovery Storage Group is disconnected and therefore not accessible to users with mail clients.

Before you can run Exmerge.exe successfully you have to grant the appropriate user permission to be able to open the store. In general nobody is able to open storage than his own. Microsoft recommends creating a new security group for it, adding the logon account to this group and then granting this group permission on the database object in Exchange System Manager. Another “quick and dirty” way to grant permissions to the appropriate group is to put them into the security group “Exchange Domain Server”. This will grant the account the permission, too.

Figure 4: Using the Recovery Storage Group

If you have successfully created the Recovery Storage Group you’ll have to complete some final steps before starting the recovery procedure. These steps are defining the path for transaction logs and system files and then adding the database to be recovered to the Recovery Storage Group by using the context menu.

Afterwards you can start your backup and restore application and choose the database to be restored. After the restore is complete, you can hopefully mount this store successfully. With this procedure you are prepared to start the Microsoft Exchange Mailbox Merge Wizard (better known as Exmerge).

After having started Exmerge.exe from command prompt just follow the instructions within the wizard to specify the export method, source and destination server. If the Recovery Storage Group is on the same Exchange server as the online database, this might be a single server. You should then choose the appropriate mailbox to be recovered and choose a temporary folder for log files. The wizard then copies the data from the mailbox into the recovery database and merges it with the corresponding mailboxes in the original storage. After this procedure is completed you can successfully use the recovered mailbox within your MAPI application.

Final conclusion

With the Exchange Server 2003 newly created Mailbox Recovery Center and the possibility to create your own Recovery Storage Group every Exchange administrator will have two more great features to easily recover lost or orphaned mailboxes within your organization. The Recovery Storage Group can successfully connect to Exchange 2000 databases, if SP3 is being applied to the Exchange 2000 Server. That means you can use these tools within a mixed environment, too.

In general these features provide a way to choose the Microsoft provided ways and tools to provide a successful plan for disaster recovery without having to buy 3^rd party tools for “brick-level” backups which would enlarge the backup schedules during the night enormously.