Topic Last Modified: 2005-11-18

The Microsoft® Exchange Server Analyzer Tool reads the following registry entry to determine whether the default setting on the LocalDeliveryMaxBatch registry value has been changed:


If the Exchange Server Analyzer finds that the LocalDeliveryMaxBatch registry value setting is manually created, changing the default Exchange server binary setting of 80, the Exchange Server Analyzer displays a non-default warning message.

By default, the LocalDeliveryMaxBatch registry value is not created during an Exchange Server installation. The LocalDeliveryMaxBatch registry value can be manually created after the Exchange Server installation to change how the Exchange Information Store internally processes and delivers messages. The Exchange server may experience problems with message transport and store performance if the following conditions are true:

It is recommended that the LocalDeliveryMaxBatch registry value be created or modified only after careful consideration. The default values, in the binaries, for Exchange server were carefully selected for optimal performance for use in most Exchange server environments. A general best practice is to address the root cause of the problem instead of modifying the default behavior of Exchange Server by manually configuring the registry. To comply with best practices, if the LocalDeliveryMaxBatch registry value already exists, you may want to delete this registry value to configure the Exchange server back to the default binary setting.

The Exchange Server Analyzer reports this configuration for informational purposes only. However, you may want to change the registry value back to the default setting by editing the registry.

This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore the registry if a problem occurs. For information about how to restore the registry, view the "Restore the Registry" Help topic in Regedit.exe or Regedt32.exe.
To correct this warning
  1. Open a registry editor, such as Regedit.exe or Regedt32.exe.

  2. Navigate to the following registry key: HKEY_LOCAL_MACHINE\Software\Microsoft\Exchange\StoreDriver\Exchange\%SMTPVirtualServerInstance%

  3. In the details pane, right-click the LocalDeliveryMaxBatch registry value, click Modify, and then change the Value data to 80. Click OK.

    To delete the LocalDeliveryMaxBatch registry value, in the details pane, right-click the LocalDeliveryMaxBatch registry value and then click Delete. Confirm the deletion of the registry value by clicking Yes in the dialog box.
  4. Close the registry editor.

  5. Restart the Exchange server.

Before you edit the registry, and for information about how to edit the registry, see Microsoft Knowledge Base article 256986, "Description of the Microsoft Windows registry" (

For more information about editing the Microsoft Windows registry, see the following Microsoft Knowledge Base articles: