Parse error: parse error in C:\wamp\www

quelqu'un pourrait M'aider , depuis un mois j'essaie de ressoudre ce probleme et j'y parviens pas.

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Parse error: parse error in C:\wamp\www\.................

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Mon code en dessous

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<?php require_once('Connections/x.php');

//catch field data

if((isset($_POST['user_name'])) || if(isset($_POST['user_password'])) || if(isset($_POST['submitted']));

//if(isset($_POST['user_name']))
$user_name = $_POST['user_name'];
//if(isset($_POST['user_password']))
$user_password = $_POST['user_password'];
//if(isset($_POST['submitted']))
$submitted = $_POST['submitted'];

if ($user_name && $user_password){

/////////////////////////////////////
$query = sprintf("SELECT * FROM users WHERE user_name='$user_name' AND user_password='$user_password'");
$result = @mysql_query($query);
$rowAccount = @mysql_fetch_assoc($result);
/////////////////////////////////////
}

if ($rowAccount)

{

echo "the record exists so you can enter";

}

elseif($submitted)

{

echo "you dont exist in the system so you not getting in !";

}

?>