Warning: mysqli_connect(): (HY000/1045): Access denied for user code example

Example 1: mysqli::real_connect(): (HY000/1045): Access denied for user 'pma'@'localhost' (using password: NO)

$cfg['Servers'][$i]['port'] = '3307';

Example 2: mysqli_real_connect(): (HY000/1698): Access denied for user 'root'@'localhost'

ALTER USER 'root'@'localhost' IDENTIFIED BY 'mysql';

Example 3: php catch mysqli_connect(): (HY000/1045): Access denied

$conn = mysqli_connect( '<server>', '<username>', '<password>',  '<database-name>');
if (!$conn) {
  // whatever processing you want to do upon error in connection
  // like log error or send an email to admin
  // I am just printing the error at the moment.
  echo mysqli_connect_errno() . ":" . mysqli_connect_error();
  exit;
}