Message size limit conflict

[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: 2010-03-25

The Microsoft Exchange Best Practices Analyzer queries the Active Directory directory service to determine the values that are set for the global message size limits. This includes values for the maximum incoming message size, the maximum outgoing message size, and the maximum number of message recipients.

Global message limits are stored in Active Directory. These limits apply to all Exchange 2007 and Exchange 2003 servers in an organization. Additionally, in Exchange 2007, organizational message limits may be set. These limits apply to all Exchange 2007 servers that run the Hub Transport role in an organization.

On an Edge Transport server, the specified limits apply only to the particular server.

When the organizational limits and the global message limits conflict, the lowest value takes precedence.

In the original release version of Exchange 2007, the initial values for the global message limits only differ from the default values when the following conditions are both true:

  • A value was specified for Sending message size, Receiving message size, or Maximum recipients in Exchange 2003.

  • The organization was upgraded from Exchange 2003 to the original release version of Exchange 2007.

Any message limit that is set in Exchange 2003 is preserved during an upgrade to the original release version of Exchange 2007.

If the Exchange Best Practices Analyzer determines that any of the global message size settings differ from the Exchange 2007 organizational message limits, a warning message is displayed.

We recommend that you set the global message size limits and their corresponding organizational message limits to the same values.

For the original release version of Exchange 2007, you can use Exchange System Manager on an Exchange 2003 server or the Active Directory Service Interfaces (ADSI) Edit tool to change global message limits.

To set global message limits
  1. Start Exchange System Manager.

  2. Expand Global Settings, right-click Message Delivery, and then click Properties.

  3. Click the Defaults tab.

  4. Configure the appropriate values for the message limits, and then click OK. By default, Exchange 2003 has the following message limit values set:

    • Sending message size - 10240

    • Receiving message size - 10240

    • Maximum recipients - 5000

To manage organizational message size limits in Exchange 2007, use the Set-TransportConfig cmdlet in Exchange Management Shell, or use Exchange Management Console to configure the Hub Transport server organization configuration properties.

To set organizational message limits
  1. Start Exchange Management Console.

  2. Expand Organization Configuration, expand Hub Transport, and then click the Global Settings tab.

  3. Right-click Transport Settings, and then click Properties.

  4. On the General tab, configure the same message limits as those used in the earlier procedure, and then click OK. By default, Exchange 2007 has the following message limit values set:

    • Maximum receive size (KB) - 10240

    • Maximum send size (KB) - 10240

    • Maximum number of recipients - 5000

For more information about how to change the global message limit, see How to Modify Exchange 2003 Global Message Size Limits in Exchange 2007 RTM.

For more information about how to manage message limits in Exchange 2007, see Managing Message Size Limits.