You are seting up a new website and you get an 403 forbidden error and this on apache error log :

AH01630: client denied by server configuration

You don’t understand because you already setup hundred of websites, you check chmod but you still get this error.

Don’t panic, since apache 2.4 you have to change the directory configuration:

<Directory />
  Options Indexed FollowSymLinks
  AllowOverride All
  Require all granted
</Directory>

and restart apache, that should do the trick.