<?php
if(!empty($_POST['username']) && !empty($_POST['password'])&& !empty($_POST['password1']))
{
    $username = mysql_real_escape_string($_POST['username']);
    $password = md5(mysql_real_escape_string($_POST['password']));
    $password1 = md5(mysql_real_escape_string($_POST['password1']));
    $email = mysql_real_escape_string($_POST['email']);
    $servername = "localhost";
    $name = "root";
    $pass = "usbw";
    $dbname = "users";
    $link = mysqli_connect($servername, $name, $pass, $dbname);
if (!$link) {
    die("Connection failed: " . mysqli_connect_error());
  }
}
    $checkusername = mysqli_query($link,"SELECT * FROM users WHERE Username = '".$username."'");
     if(mysqli_num_rows($checkusername) == 1)
     {
        echo "<h1>Error</h1>";
        echo "<p>Sorry, that username is taken. Please go back and try again.</p>";
     }
     else
     {
        $registerquery = mysqli_query($link,"INSERT INTO users (Username, Password, EmailAddress) VALUES('".$username."', '".$password."', '".$email."')");
        echo($registerquery);
        if($registerquery)
        {
            echo "<h1>Success</h1>";
            echo "<p>Your account was successfully created. Please <a href="index.php">click here to login</a>.</p>";
        }
        else
        {
            echo "<p>Sorry, your registration failed. Please go back and try again.</p>";
        }
     }
mysqli_close($link);
?>