Can somebody tell me what is worng

<pre><?php

		error_reporting(E_ERROR | E_WARNING | E_PARSE | E_NOTICE);
		
		
		if(isset($_POST['register_user']))
		{
			//capture the variable from the form and store in php variables
			
			
			$title=$_POST['title'];
			$fullname=$_POST['fullname'];
			$lastname=$_POST['lastname'];
			$screenname=$_POST['screenname'];
			$email=$_POST['email'];
			$gender=$_POST['gender'];
			$address=$_POST['address'];
			$mypwd=$_POST['mypwd'];
			
			//connecting to the server
			
			include'db_server.php';
			
			$conn = mysqli_connect($db_host,$db_username,$db_password) or die (mysqli_connect_error());
			
			//select the database you want to query
			
			mysqli_select_db($conn, 'national_wonders') or die (mysqli_error($conn));
			$sql = "SELECT * FROM members WHERE screenname='$screenname'";
			$result = mysqli_query($conn, $sql) or die ("ERROR:" .mysqli_error());
			$rowcount = mysqli_num_rows($result);
			
			if($rowcount >= 1)
			{
				echo"<script type=\"text/javascript\">
					alert('Username already exits!!');
					window.location=\"../php/popup.php\";
					</script>";
			}
			else
			{
				//insert data into table
				
				$sql = "INSERT INTO members
				VALUES('$title', '$fullname', '$lastname', '$screenname', '$address', '$email', '$gender',  'md5('$mypwd))";
			
				if(mysqli_query($conn,$sql))
				{
					echo"<script type=\"text/javascript\">
					alert(Welcome);
					window.location=\"login.php\";
					</script>";
				}
				else
				{
					echo "Error inserting values into database";
				}
				
			
			}
			
		}	
			
?>