PHP on Windows loads its configuration file php.ini during the startup of the process php-cgi.exe. When PHP is run on IIS via FastCGI the php-cgi.exe processes are re-used to handle many requests. If configuration settings in php.ini file get updated, those changes will not be picked up by php-cgi.exe processes until the processes are recycled or restarted by IIS FastCGI module. This means that any time you change the PHP configuration you have to manually recycle IIS Application Pools that use PHP. This post explains how to configure FastCGI in IIS so that PHP configuration changes take effect right away without the need to manually recycle or restart the IIS Application Pools.