I ran into a stupid problem, by changing the settings for permalinks to a WordPress (switching the classic PHP request to URL SEO) i get a “404 error page not found”. After checking that my apache to have the mod_rewrite enabled and .htaccess file was been created by WordPress itself, i tried to investigate into the configuration of Apache.

Actually the configuration of the root directory report the value:
AllowOverride None
changed in:
AllowOverride All
The problem was solved, but have wasted me  lot of time …