Topic Last Modified: 2005-11-18

The Microsoft® Exchange Server Analyzer Tool reads the following registry entry to determine the setting for the SystemPages value:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\SystemPages

The Exchange Server Analyzer also queries the Win32_OperatingSystem Microsoft Windows® Management Instrumentation (WMI) class to determine the value of the OSProductSuite key. The value of this key corresponds to a specific version of a Microsoft Windows operating system.

If the Exchange Server Analyzer finds the value for SystemPages is not set to 0 on an Exchange Server computer that is running Microsoft Windows Server™ 2003 that is not part of a Microsoft Windows Small Business Server 2003 installation, a warning is displayed.

When you are running Exchange Server 2003 Service Pack 1 (SP1) on Microsoft Windows Server 2003 with 1 GB or more of RAM, it is recommended that you set the SystemPages registry key to 0. This recommendation contrasts with the recommendation for Microsoft Windows 2000 Server, which is to set SystemPages to a value between 24000 and 31000.

On a Windows Server 2003 computer that is not part of a Microsoft Windows Small Business Server 2003 installation, you should never set the SystemPages registry value to anything other than 0. Changing it prevents the system from calculating an optimal value for your system and adjusting the value when your system changes.

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.
The ramification for setting the SystemPages registry value on computers running Windows Server 2003 is that the maximum size of the paged pool will be lower. This can lead to paged pool exhaustion and server instability.

To correct this warning

  1. Open a registry editor, such as Regedit.exe or Regedt32.exe.

  2. Navigate to: HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management

  3. In the right pane, double-click SystemPages.

  4. In the Value data field, type 0, and then click OK.

  5. Exit the registry editor and restart the computer for the change to take effect.

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

For more information about optimizing memory for Exchange Server, see the following Knowledge Base articles: