I am using SugarCRM 4.2.1b on an IIS web server. Everything seems to work fine so far. However when I login to the admin module and try to change system wide settings such as date format etc. I get the following error:

Warning: fopen(config_override.php): failed to open stream: Permission denied in \crm\modules\Configurator\Configurator.php on line 63

Since config_override.php did not exist by default, I created one with two empty php tags. I have also given IUSER_Machine account full permissions to the modules directory, its subdirectories and files. Configurator.php file also has full write and read permissions. I still get this error. Does anyone know how to fix this?