Thank you for your answer.
I am the host.
However, not matter if I set manually the config file to use curl:
'xs_usecurl' => '1',
The server still return the same error.
Beside this, PHP is correctly configured to allow fopen:
allow_url_fopen = Onand the domain name has been whitelisted in mod_security config.
Unfortunately, your script is ioncubed so I can't check exactly the piece of code where this error is reported.
Any further help would be greatly appreciated as long as I can't use at all anymore the script.