First, you need to add a symlink to the mod-enabled directory
sudo ln -s /etc/apache2/mods-available/rewrite.load /etc/apache2/mods-enabled/
Then you should open default site configration
sudo gedit /etc/apache2/sites-enabled/000-default
And replace Allow Override None with Allow Override all
Directory /var/www/>
Options Indexes FollowSymLinks MultiViews
AllowOverride all
Order allow,deny
allow from all
End restart the apache
sudo /etc/init.d/apache2 restart
