A database reached the maximum allowed size


Topic Last Modified: 2007-11-16

The Microsoft Exchange Server 2007 Management Pack for Operations Manager monitors the Windows Application log on computers that are running Exchange Server 2007 and generates this alert when the event or events specified in the following Details table are logged.

To learn more about this event, do one or more of the following:

  • Review the description of the event that includes the variables specific to your environment. From the Operator Console, select this alert, and then click the Properties tab.

  • Review all events that have been logged that meet the criteria of this Operations Manager alert. From the Operator Console, click the Events tab, and then double-click the event in the list for which you want to review the event description.


Product Name


Product Version

8.0 (Exchange Server 2007)

Event ID


Event Source


Alert Type

Critical Error

MOM Rule Path

Microsoft Exchange Server/Exchange 2007/Mailbox/Information Store

MOM Rule Name

A database reached the maximum allowed size. Attempting to dismount the database.

This Error event indicates that the disk volume that contains a Microsoft Exchange Server database is either out of disk space or has reached the maximum allowed database size. With Microsoft Exchange Server 2007, you can configure the maximum size of the Exchange 2007 database based on the Exchange version that you have installed.

To resolve this error, do the following:

  • You can configure the maximum size of the Exchange 2007 database. See the topic Database Size Limit Configuration and Management in the Technical Reference Guide for Exchange Server 2003. The Exchange 2003 content describes how to change the value applies to the Exchange 2007 server.

  • If you have not exceeded the database limit, determine whether the specified disk is full. If the disk is full, you must reduce the amount of data on the disk, and then restart the Microsoft Exchange Information Store service. You can take action to free up disk space, such as the following:

    • If the database transaction log files are on the same disk as the Exchange database, it is possible that too many log files have accumulated. This situation can be caused by excessive database usage during a mailbox move or other operation, or it can be caused by incorrectly performing backups. The correct method to remove database transaction log files is to perform an online backup. An online backup commits all of the log files to the database and then removes the log files from the disk. For more information about how to remove the database transaction log files, see Microsoft Knowledge Base article 240145, How to remove the Exchange Server transaction log files.

    • If the database and transaction log files are on the same disk, consider moving the logs to another disk.

    • If the database has become too large for the disk, consider moving the database to a new disk.

    • If there are other files on the disk, consider deleting or moving those files.

    • If there are other Exchange databases on the disk, consider moving those databases.

    • Reclaim disk space in the Exchange database by using the Exchange Server Database Utilities (Eseutil.exe). To determine how much free space is in the database, check event ID number 1221 or 1222. For more information about using Eseutil to defragment the Exchange database, see Eseutil /D Defragmentation Mode.

    • You can use the Database Troubleshooter tool included with Microsoft Exchange 2007 to clean up the database transaction log files or move the Exchange database. You can run the Database Troubleshooter tool from the Toolbox in the Exchange Management Console.

To search the Microsoft Knowledge Base articles based on criteria that generated this alert, visit the Search the Support Knowledge Base (KB) Web site.

To review Exchange 2007 event message articles that may not be represented by Exchange 2007 alerts, see the Events and Errors Message Center.

If you are not already doing so, consider running the tools that Microsoft Exchange offers to help administrators analyze and troubleshoot their Exchange environment. These tools can help you make sure that your configuration is in line with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. Go to the Toolbox node of the Exchange Management Console to run these tools now. For more information about these tools, see Toolbox in the Exchange Server 2007 Help.