Respuesta Cita: That is due to negative settings in this directive -> allow_url_fopen in the php.ini file. I had no idea they were doing it that way. More and more hosts are turning this off every day as poorly thought out usage could result in disaster if you are opening some else's pages.
You could try adding:
ini_set('allow_url_fopen', 'on');
at the top of index.php. You may be allowed this overide.
Me respondo yo mismo!!!
Por si a alguien le puede servir.
Quim