IIS is Creating 32-bit processes on a 64-bit Machine

[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 http://go.microsoft.com/fwlink/?linkid=34707.]  

Topic Last Modified: 2007-05-03

The Microsoft Exchange Server Analyzer tool queries the Internet Information Services (IIS) metabase for the value of the w3svc/AppPools/Enable32BitAppOnWin64 metabase property on all 64-bit Windows Server 2003 Service Pack 1 (SP1) servers that are running Exchange Server 2007 to determine whether IIS is configured to create 32-bit worker processes.

A value of 1 (true) indicates that IIS is configured to create 32-bit worker processes. A value of 0 (false) indicates that IIS is configured to create 64-bit worker processes**.**

If the Exchange Analyzer determines that the value for the w3svc/AppPools/Enable32BitAppOnWin64 metabase property is set to 1 (true), the Exchange Analyzer displays an error. This error indicates that IIS is configured to create 32-bit worker processes on a 64-bit Windows server that is running Exchange 2007. This configuration will cause the Exchange 2007 virtual directories to become dysfunctional.

To address this error, configure IIS to create 64-bit worker processes on the 64-bit Windows Server 2003 (SP1) server that is running Exchange 2007.

To switch IIS to 64-bit mode

  1. Open a command prompt.

  2. Type the following:

    cscript c:\inetpub\adminscripts\adsutil.vbs SET /w3svc/AppPools/Enable32BitAppOnWin64 False

  3. Press enter

For more information about running IIS 6.0 32-bit worker processes on 64-bit Windows Server 2003 SP1 server, see Microsoft Knowledge Base article 895976 "Windows Server 2003 SP1 enables WOW64 compatibility for 32-bit Web applications in IIS 6.0" (http://go.microsoft.com/fwlink/?LinkId=3052&kbid=895976).