The utility returns in SP1

Exchange Server 5.5 Service Pack 3 (SP3) introduced Mailbox Manager, a utility that lets you automate cleaning up users' mailboxes, if they don't or can't do it themselves. Mailbox Manager lets you delete or move items within any selected user's—or group of users'—mailbox on a scheduled basis. The utility lets you reduce the size of your Exchange Server 5.5 databases and free important space so that you can restore data more quickly as a result of not having redundant data in your users' mailboxes. For a detailed explanation of the Exchange Server 5.5 version of Mailbox Manager, see Tony Redmond, "Control Mailbox Size with Mailbox Manager," November 1999.

One common use of Mailbox Manager is to automatically move data from the Sent Items folder for a set period (e.g., 30 to 60 days). The Sent Items folder tends to get very large because users don't realize that they keep huge amounts of data in that folder. The Sent Items folder holds a copy of all the objects a user has sent to others, including large attachments such as Microsoft PowerPoint presentations or Microsoft Word documents. By default, attached files are usually redundant, because they're stored somewhere else on your local drive or a network drive. Another Mailbox Manager option is to delete or move all items older than X days.

Exchange Server 5.5 Mailbox Manager
In Exchange Server 5.5, you can install the Mailbox Manager component separately on one server in a site, and it can manage any server in that site. The utility can automatically move items from virtually all mailbox folders (e.g., Inbox, Sent Items, Deleted Items) into one of two dumpsters: the Deleted Items folder or System Cleanup Folders. Administrators opt to move the items to the Deleted Items folder because users either manage this folder well or set Microsoft Outlook to empty the Deleted Items folder when they exit Outlook.

Exchange treats messages moved to the Deleted Items folder as items that a user deletes manually. If you enable deleted-item retention on the servers, users can restore a particular deleted item without administrator involvement.

The other option is to move the items into a new location called System Cleanup Folders. System Cleanup Folders are a partial replica of the mailbox's folder hierarchy that's created in the root of the mailbox. The advantage of these folders is that the item moved doesn't lose its information in the original location (i.e., an item from the Inbox folder is moved into System Cleanup Folders\Inbox). Because this method lets users easily locate deleted messages and potentially restore them to their original location, some administrators believe this option is the best way to use Mailbox Manager. A disadvantage, however, is that administrators must also manage the System Cleanup Folders with Mailbox Manager because users neglect to clean up this folder, too.

Microsoft didn't include an updated version of Mailbox Manager in Exchange 2000 Server, so companies that had spent time implementing the Exchange Server 5.5 Mailbox Manager were out of luck. Although Exchange 2000 supports multiple databases in multiple storage groups (SGs), filling the Exchange databases with redundant data won't help support the higher service level agreements (SLAs) that enterprises require today.

Exchange 2000 Mailbox Manager
The good news is that Mailbox Manager reappears in Exchange 2000 SP1 as a new recipient policy. Mailbox recipient policies enforce corporate mail-retention policies and create additional email addresses for users. By default, Mailbox Manager is installed (but disabled) on all servers you upgrade to SP1.

As it has with many other tasks, Microsoft has changed the way you operate and configure Mailbox Manager. The utility is now a little more complicated to set up and manage, but it's still a useful tool. With the new Mailbox Manager policy, you configure Mailbox Manager to move or delete messages from specific (or all) folders in users' mailboxes. For each Mailbox Manager policy you create, you can define the membership (or filter) for the users you want to include in the policy through a Lightweight Directory Access Protocol (LDAP) query interface. The policy also lets you select whether you want to delete messages based on age, size, or both. You can notify users that their mailbox has been cleaned, and you can have Exchange send a report of the actions to an administrator.

Unlike Mailbox Manager in Exchange Server 5.5, the new version lets you process only local mailboxes. Therefore, you must enable the utility on every server on which you want to use a certain policy. In addition, you can implement and manage the Exchange 2000 Mailbox Manager only on servers with Exchange 2000 SP1 installed. Servers without SP1 will show the Mailbox Manager policy as an email address recipient policy, but you won't be able to use it.

How It Works
Mailbox Manager is a recipient policy, which is a collection of configuration settings that let you define Active Directory (AD)­wide system policies. When you implement a recipient policy, you can change options or enforce settings on many objects in one operation.

Mailbox Manager in Exchange 2000 uses mailbox recipient policies to enforce defined policies on all mailboxes that are members of the policy. Using the policy's LDAP query interface, you configure Mailbox Manager to search all users' mailbox folders or select only a particular server or one Exchange Mailbox Store. Figure 1 shows the first screen that appears when you create a new mailbox recipient policy.

To create a new mailbox recipient policy, open the Microsoft Management Console (MMC) Exchange System Manager snap-in. Right-click the Recipient Policies object, right-click the object, and select New, Recipient Policy, as Figure 2 shows. In the New Policy dialog box, select the Mailbox Manager Settings check box.

Setting Policies
As you can in the Exchange Server 5.5 version, you can still set the Mailbox Manager policy option to move items to Deleted Items or System Cleanup Folders. However, the Exchange 2000 version also lets you either generate a report only or delete the items immediately, as Figure 3 shows. Depending on which process you select, Mailbox Manager performs certain actions on messages. Table 1 shows the actions and their functions.

By default, Mailbox Manager selects all folders, the message age limit is 30 days, and the message size is 1024KB. However, you can customize these settings in the Folder Retention Settings dialog box by selecting the folder you want to modify and clicking Edit. When you select a folder type, the policy searches the default Outlook folder (e.g., Contacts) and all user-created folders based on the root folder (e.g., a user-created new Personal Contacts folder with the content type set to Contacts).

Another new feature lets you exclude a particular type of object from the policy, regardless of the folder the object resides in. For example, you might not want to use the rules on a Public Folder application, on a custom form, or maybe even in Calendar items. (By default, the policy deletes the selected folder's message class from the selected folder, but you might, for example, have contact information saved in another folder that you want to preserve.) To exclude a specific message class, you select the Exclude specific message classes check box on the Mailbox Manager Settings (Policy) tab, which Figure 3 shows, and customize the classes you want to exclude (e.g., IPM.CompanyClass.Post, IPM.CompanyClass.Contact). You can also use wildcards to exclude all classes or subclasses (e.g., IPM.CompanyClass.*).

One characteristic I don't like is that you ultimately end up with several (10 or more) recipient policies just because you want to keep your system healthy. For example, you might want to have different policies on different SGs. You'll also have at least as many policies as you have servers you want to manage because the Exchange 2000 version doesn't let a Mailbox Manager policy span servers. Having to maintain multiple policies means that you must spend more time not only designing and configuring them correctly but also managing them.

Enabling Policies
To enable Mailbox Manager, use Exchange System Manager to set up a mailbox recipient policy on objects. To filter membership and configure Mailbox Manager parameters, go to the Recipient Policies object, which I discussed previously. To set the Mailbox Manager properties on each server you want Mailbox Manager to run on, use the Mailbox Management tab in the server's Properties dialog box, as Figure 4 shows. This step is necessary because Mailbox Manager can handle only users that belong to the selected server. You also schedule the process on the Mailbox Management tab. Because Mailbox Manager creates performance overhead, select a schedule that doesn't conflict with other resource-intensive tasks, such as backups or antivirus scanning.

A new feature in the SP1 version is that when you enable Mailbox Manager on a server, you can choose to produce a summary report or a detailed report and send it to a designated administrator mailbox. Figure 5 shows a summary report. Web Figure 1 on the Exchange Administrator Web site (http://www.exchangeadmin.com) shows a truncated version of a detailed report.

Finally, you can run the cleanup process manually at any time by right-clicking the server on which you want to run the process and selecting Start Mailbox Management Process from the context menu. This action starts the management process immediately.

A Welcome Addition
The inclusion of Mailbox Manager in Exchange 2000 SP1 is welcome. I find the tool extremely useful in preventing the messaging system from becoming overloaded. Administration of Mailbox Manager has become more complex, and the process might scare off some administrators. However, when you understand the concepts, the process is straightforward, although you must carefully plan the schedules for each server.