This Exchange server is running with Physical Address Extensions enabled

[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: 2010-11-19

The Microsoft® Exchange Server Analyzer Tool queries the Win32_OperatingSystem Microsoft Windows® Management Instrumentation (WMI) class to determine the values for the following keys:

  • PAEEnabled   The value of this key indicates whether Physical Address Extension (PAE) is enabled. A value of True indicates that PAE is enabled and a value of False indicates that PAE is not enabled.

  • Version   The value of this key indicates the version of the Microsoft Windows operating system that is running on the computer. A value of 5.0.2195 indicates that a Microsoft Windows 2000 Server operating system is running and a value of 5.2.3790 indicates that a Microsoft Windows Server™ 2003 operating system is running.

  • ServicePackMajorVersion   The value of this key indicates the major version number of the installed Windows service pack.

The Exchange Server Analyzer also queries the CIM_Datafile WMI class for the minor version of ntoskrnl.exe running on the system to determine if security update MS04-032 is installed on the computer. If the minor version of ntoskrnl.exe is 174 or less, it indicates that MS04-032 is not installed. If the minor version of ntoskrnl.exe is greater than 174, it indicates that MS04-032 is installed.

If the Exchange Server Analyzer finds the value for PAEEnabled set to True for an Exchange Server running on Windows Server 2003 that does not have security update MS04-032 installed, an error is displayed. This error indicates that the computer is susceptible to a known issue that can cause the Microsoft Exchange Information Store service (Store.exe) to crash.

Exchange Server does not make use of PAE. PAE enables Windows to access more than 4 gigabytes (GB) of physical memory. Exchange Server cannot use more than 4 GB of physical memory, and there is no benefit to installing more than 4 GB of RAM on a computer that is dedicated to running Exchange Server. PAE is enabled when the /PAE startup switch is present in the Boot.ini file on startup or when the Windows Server 2003 operating system detects hot-add memory devices. Windows Server 2003, Enterprise Edition and Windows Server 2003, Datacenter Edition automatically enable PAE only if the server is using hot-add memory devices.

To correct this error by installing the MS04-032 update

  1. To obtain the MS04-032 update, see the Microsoft Knowledge Base article 840987, "MS04-032: Security update for Microsoft Windows" (

  2. Completely back up the system.

  3. Apply the update, and then restart the computer for the update to take effect.

For more information about PAE, see the following Knowledge Base articles:

For more information about the /NOPAE switch in Boot.ini, see the MSDN article, "/nopae" (