by Guillermo Madero S..
Hi Aaricia,
I'd bet it is a server configuration issue. Maybe you'd like to take a look at the following:
http://learn.iis.net/page.aspx/246/using-fastcgi-to-host-php-applications-on-iis/
http://learn.iis.net/page.aspx/697/configure-php-process-recycling-behavior/
php-cgi.exe is the CGI executable that can be used when running PHP on IIS via CGI or FastCGI. It handles or processes php files.