Thanks but is like before for me as I am mot an expert of fixing this issues. I don't know if I can pubblish all the error because of the hackers.
Anyway my question was about which support I have to ask for fixing the problem as in the message is contained the name of my theme (which is not a free one), this wordpress forum (abou taxonomy) or the support of my WP Multilingual plugin as the site loads very slow when I try to change language.
This is so weird to me...I don't know which can help me to solve the issue. XD