404 Not Found The requested URL was not found on this server

This problem come usually , Then at short how we can solve, directly i will give you solution.

In Ubuntu I did not found httpd.conf, It may not exit longer now. Edit in apache2.conf file 

cd /etc/apache2 
sudo vi apache2.conf

Change the below line

<Directory /var/www/>
        Options Indexes FollowSymLinks
        AllowOverride None
        Require all granted
</Directory>

AllowOverride All

<Directory /var/www/>
        Options Indexes FollowSymLinks
        AllowOverride All
        Require all granted
</Directory>

Now restart apache2 with below command

sudo systemctl restart apache2

Now its done, Hope this will help you.