• The Web Service Extension needs to point to %WINDIR%\SysWOW64\inetsrv\fcgiext.dll.
• The .php extension on the website also needs to point to %WINDIR%\SysWOW64\inetsrv\fcgiext.dll.
• The fcgiext.ini file must also be located in %WINDIR%\SysWOW64\inetsrv.  Otherwise you will get a 500 error from FastCGI saying it cannot find the configuration file.

Note that the fcgiconfig.js script is only installed in %WINDIR%\system32\inetsrv.  I was able to create a fcgiconfigwow64.js file that points to the correct files.  The script needs to have at least an ini file with the “[Types]” section in the %WINDIR%\SysWOW64\inetsrv directory.  It also needs to be located under %WINDIR%\system32 as it doesn’t support running under Wow64.  You just need to change the following 2 lines near the top of the script.

From:

var g_iniPath       = g_Shell.ExpandEnvironmentStrings( "%WinDir%\\system32\\inetsrv\\fcgiext.ini" );
var g_extensionPath = g_Shell.ExpandEnvironmentStrings( "%WinDir%\\system32\\inetsrv\\fcgiext.dll" );

To:

var g_iniPath       = g_Shell.ExpandEnvironmentStrings( "%WinDir%\\SysWOW64\\inetsrv\\fcgiext.ini" );
var g_extensionPath = g_Shell.ExpandEnvironmentStrings( "%WinDir%\\SysWOW64\\inetsrv\\fcgiext.dll" );