About a year ago I wrote an article about how to enable per-site PHP configuration on IIS with FastCGI. The instructions in that article required some non-trivial manipulations of IIS and FastCGI configuration settings. At that time it was one of the primary options for enabling per site php.ini support (other option was to use the htscanner extension for PHP). Now, with PHP 5.3 final release available, it is much simpler to implement the same configuration because PHP 5.3 has built-in support for per-directory INI settings and for user-defined INI files. This post describes how to use these features of PHP 5.3 with IIS to enable per-site and per-directory PHP configuration.