mailcheck.php

<?php 

ini_set( 'display_errors', 1 );
error_reporting( E_ALL );

$from = "[email protected]";
$to = "[email protected]";
$subject = "PHP Mail Test script";
$message = "This is a test to check the PHP Mail functionality";
$headers = "From:" . $from;

if (mail($to, $subject, $message, $headers)) {
  echo "OK";
} else {
  echo "Err";
}