XAMPP not accessing MySQL

[beboYasu]

Hi there,
I developed a web page testing it in XAMPP 1.7.3 without any problem. I uploaded a beta version of the web application a few days ago. After that I improved the application on localhost but suddenly when I click a page that does some query to the DDBB i receive a white page and an error about charset, as it doesn't load header_view.php and page_view.php.
To make sure it's not a code issue I downloaded all previously uploaded application from the site, but it's still not working on localhost.

The online application works but the same application running on localhost gives white pages if consulted the DDBB.(login page and main page work perfectly)

I think its a local server problem. Any suggest?
Thanks in advance