Ok, found the solution,

<Directory /path/to/site>
     #add the following setting to allow .htaccess in your web dir to work
     AllowOverride All

     #other settings ---

</Directory>

and thats in the /etc/apache2/apache2.conf file

and mod_rewrite is enabled…

this is unbelievable ! I just dont have the solution, anybody please help !!
My .htaccess

# BEGIN WordPress
<IfModule mod_rewrite.c>
Options +FollowSymlinks
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

rewrite_module is on

and still 404....

same her how to solve this problem

be sure to add mod_rewrite and restart apache after that

sudo a2enmod rewrite

sudo service apache2 restart