Monday, June 28, 2010

Running IIS 6 in 32-bit Mode on Windows Server 2003 64-bit

You can set IIS 6 to run in 32-bit mode with the following command:

%SystemDrive%\inetpub\AdminScripts\adsutil.vbs set w3svc/AppPools/Enable32bitAppOnWin64 1

After setting IIS to enable 32-bit appilcations, the following exception may occur:

ISAPI Filter 'c:\WINDOWS\Microsoft.NET\Framework64\v2.0.50727\aspnet_filter.dll' could not be loaded due to a configuration problem. The current configuration only supports loading images built for a x86 processor architecture. The data field contains the error number. To learn more about this issue, including how to troubleshooting this kind of processor architecture mismatch error, see

This is due to the fact that the .NET framework needs to be registered with IIS after enabling 32-bit mode.  Note, after enabling 32-bit mode and re-registering the framework, you will have to restart IIS.  Also, you may need to go to the Web Service Extensions and Allow the ASP.Net 2.0 (32-bit) extension.

To register the .NET framework with IIS, run the following command:

%windir%\Microsoft.NET\Framework\v2.0.50727\aspnet_regiis -i