数据库插入注册失败

Question

        <?php require 'header.inc.php';      
           require 'connect.inc.php';    ?> 
     <?php
      $reg = @$_POST['reg'];
      $fn        =   "";
      $ln        =   "";
      $un        =   "";
      $em        =   ""; 
      $pswd      =   ""; 
      $d         =   "";
      $u_check   =   ""; 

      $fn   =   strip_tags(@$_POST['fname']);
      $ln   =   strip_tags(@$_POST['lname']);
      $un   =   strip_tags(@$_POST['uname']);
      $em   =   strip_tags(@$_POST['email']); 
      $pswd =   strip_tags(@$_POST[ 'pass']);  
      $d = date('Y-m-d');
    if($reg){
      if($fn&&$ln&&$un&&$em&&$pswd){
      $u_check = mysql_query("SELECT uname FROM users WHERE uname='$un'");
      $check = mysql_num_rows($u_check);
      if ($check == 0) {
        if (strlen($un)<4||strlen($fn)<4||strlen($ln)<4) {
            if (strlen($un)>20||strlen($fn)>20||strlen($ln)>20) {
                echo "<div id=\"errormsg\"> <p>username/first name/last should not be over 20 characters</p> </div>";
            }else {
                $pswd = md5($pswd);
                $query = mysql_query("INSERT INTO users VALUES ('','$un','$fn','$ln','$em','pass')");
                die("welcome to vydoo");
            }
        }else {
            echo "<div id=\"errormsg\"> <p>username/first name/last should not be under 4 characters</p> </div>";
        }
      }else {
        echo "<div id=\"errormsg\"> <p>Username is allready taken</p> </div>";
      }
      }else {
         echo "<div id=\"errormsg\"> <p>Please fill in all fields</p> </div>";
      }
    }
      ?>
      <div class="content">
   <div class="infos">
    <p class="w">Sign Up and discover the great community</p>
    <p class="s">Sign up in few steps , its free and unlimited</p>
   </div>
    <form class="form" method="POST">
        <input class="Firstname"  type="text"        name="fname"       placeholder="Fisrt name">
        <input class="Lastname"   type="text"        name="lname"       placeholder="Last name">
        <input class="username"   type="text"        name="uname"       placeholder="Usename">
        <input class="email"      type="email"       name="email"       placeholder="Email">
        <input class="pass"       type="password"    name="pass"        placeholder="Password">
        <input class="submit"     type="submit"      name="reg"         valueenter code here="Sign In">
    </form>      

我不向数据库发送信息！问题在哪里，我纠正了那里的每一个错误，我无法找到问题所在，我已经问过这个问题，但是用不同的代码，现在我找不到我的错误代码