@acrylianI really apologize, but I can not use the answer in the previous argument: it does not send anything! (Not my problem I even changed the pc) I'm forced to open a new post.
Thanks a lot for the answer.
I've tested the issue in the following browsers:
Chrome
Ie11
Edge
Debugging the site is empty, there is nothing. I reinstalled the system in the hope of adjusting. First, it was impossible to run fopen in the log, but it is now empty by modifying the zpdata permissions. Unfortunately I can not see server errors in a free site (encrimi.altervista.org). If necessary, I can give you access credentials.
Comments
Nevertheless I think your answer about the free webspace is probably the reason for your trouble. Probably you run into a limit of form elements on POSTing the data. That is quite common issue for such free hosts to be limited everywhere.
I really recommend to consider to get a proper webspace as in the long run you will have more fun (this is not only for Zenphoto but other open source cms as well). I don't know webhosts in Italy but that surely does not need to be expensive. Over here in Germany you get very suitable webspace for around 3-5 Euros / month.
Btw, I assume that your issue happens with or without TinyMCE as that itself doesn't change the forum posting issue I suspect you have.