https://expressionengine.com/forums/archive/topic/167202/requested-url-was-not-found-on-this-server/P15

apache2.conf

 

    Require all granted

    AllowOverride All

https://stackoverflow.com/a/49408029/11971064

Try this to your .htaccess file:

  RewriteEngine On
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteRule ^(.*)$ index.php?/$1 [L]

https://stackoverflow.com/a/39261712/11971064

I know I am late, but this will help someone.

Check if rewrite engine is enabled.

If not, enable rewrite engine and restart server.

sudo a2enmod rewrite
sudo service apache2 restart