Hi guys,

When I try to run the setup on this message:

Zenphoto ha rilevato un cambiamento nella propria installazione.
Il software del proprio server è cambiato da Apache/2.4.9 (Unix) mod_fcgid/2.3.9 a Apache/2.4.9 (Unix) mod_fcgid/2.3.9.
Il software del database è cambiato da MySQLi 5.5.36 a MySQLi 5.5.36.
La modifica rilevata non è critica ma si consiglia di eseguire setup alla prima occasione.

I receive this message:

Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator at postmaster@claudioaffinito.it to inform them of the time this error occurred, and the actions you performed just before this error.
More information about this error may be available in the server error log.

Please, there is anyone that can help me with a step by step guide to solve my issue? (I am a newbie)

Thank you in advance!
Claudio

It is most certainly a missing or wrong htaccess file.

ok, How can I solve?

Run setup again. It can be anything else like permissions though. See also here:
http://www.zenphoto.org/news/general-contributor-guidelines#reporting-bugs