Fatal error: Uncaught mysqli_sql_exception: Access denied for user 'root'@'localhost' in /var/www/html/demos/email_activation/db.php:7 Stack trace: #0 /var/www/html/demos/email_activation/db.php(7): mysqli_connect() #1 /var/www/html/demos/email_activation/index.php(2): include('...') #2 {main} thrown in /var/www/html/demos/email_activation/db.php on line 7