Move User Mailboxes to Another Server

[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at]  

Topic Last Modified: 2006-09-06

The Microsoft® Exchange Server Analyzer Tool has determined that your server currently has a higher user load than it can support efficiently. The current user load is causing performance issues. It is recommended that you move users to another location by moving a small number of them (typically five percent of your total users) each night until the performance issues are resolved.

This approach is recommended because one of the following issues has occurred:

  • Some Exchange database files are on disks which are at or beyond the limit of their throughput capacity.

  • Other server resources (such as memory or CPU) are over capacity.

  • A disk is over capacity, which means that the disk subsystem that currently supports one or more of your Exchange stores has an average disk I/O latency that exceeds current recommended levels. You should move five percent of your users to a database on a different disk subsystem until the problem is resolved. If the database drives are a bottleneck, move the users to a database that is located on a different drive. If a storage group drive is the bottleneck, move the users to a database in another storage group that is located on another database. If the drives are shared by another resource, another possible solution is to reduce the load of other applications on those drives.

  • Your physical server is over capacity. You currently do not have enough processor or memory to support the server load that your users are generating. You should move five percent of your users to another server until the performance problems are resolved.


While the Exchange clients are not required to be disconnected from their mailboxes during a move mailbox operation, it is recommended that the move take place when Exchange client activity is low, such as off peak hours, to avoid possible service disruption.

To move mailboxes on Exchange Server 2003

  1. Start Exchange System Manager on the Exchange Server 2003 computer where you want to run the process.

  2. Double-click Servers, and then locate the server container where the mailboxes of the users are located.

    For example, if you want to move mailboxes from the default storage group and mailbox store, double-click First Storage Group, double-click Mailbox Store, and then click Mailboxes.

  3. In the details pane, click the mailboxes you want to move.

  4. Right-click the selected users, and then click Exchange Tasks.

  5. In the Exchange Task Wizard, click Next.

  6. On the Available Tasks page, click Move Mailbox under Select a task to perform, and then click Next.

  7. On the Move Mailbox page, in the Server list, click the server you want, and then, in the Mailbox Store list, click the mailbox store you want.

  8. Click Next.

  9. Configure how you want any corrupted messages that are found during the move to be handled, and then click Next.

  10. Click Next.

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