Register Script v15 HILFE

Register.php
PHP-Code:
<?php
require('./configs/reg_conf.php');
function doesUsernameExist($name){
$exit = FALSE;
$result = @mssql_query("SELECT * FROM ACCOUNT_TBL WHERE account='$name'");
if (mssql_num_rows($result) != 0){
$exit = TRUE;
}
return $exit;
}

if(isset($_POST['submit'])){
$user = preg_replace ("[^A-Za-z0-9]", "", $_POST['username']);
$pass = preg_replace ("[^A-Za-z0-9]", "", $_POST['password']);
if($_POST['username'] == ""){
echo '<font color="red">Enter a user.</font><br /><br />';
}
else if($_POST['password'] == ""){
echo '<font color="red">Enter a password.</font><br /><br />';
}
else if ((strlen($_POST['username']) > 16) || (strlen($_POST['username']) < 3)){
echo '<font color="red">The user should be 3 to 16 characters.</font><br /><br />';
}
else if ((strlen($_POST['password']) > 16) || (strlen($_POST['password']) < 3)){
echo '<font color="red">The password should be 3 to 16 characters.</font><br /><br />';
}
else if($_POST['username'] != $user){
echo '<font color="red">User with invalid characters.</font><br /><br />';
}
else if($_POST['password'] != $pass){
echo '<font color="red">Password with invalid characters.</font><br /><br />';
}
else {
$pass = md5('kikugalanet' . $pass);
if(!doesUsernameExist($user)){
$stmt = mssql_init('webCreateAcc', $link);
mssql_bind($stmt, '@account', $user, SQLVARCHAR, false, false, 15);
mssql_bind($stmt, '@password', $pass, SQLVARCHAR, false, false, 36);
mssql_bind($stmt, '@birthday', $bday, SQLVARCHAR, false, false, 120);
mssql_free_statement($stmt);
echo '<font color="Green">Register Successfull.</font><br /><br />';
}
else {
echo '<font color="red">User already Exist.</font><br /><br />';
}
}
mssql_close();
}

echo '<form action="#" method="post">';
echo 'Username: <input type="text" name="username" /><br />';
echo 'Password: <input type="password" name="password" /><br />';
echo 'Birthday: <input type="birthday" name="birthday" /><br />';
echo '<input type="submit" name="submit" value="Register" />';
echo '</form>';

?>



configs/function.php
PHP-Code:
<?php

function exist($account){
$sql = "SELECT * FROM ACCOUNT_TBL WHERE account='".$account."'";
$result = mssql_query($sql);
if(!$result) {
die("MSSQL Error");
}
$check = mssql_num_rows($result);
return $check;
}

function existip($ip){
$sql = "SELECT * FROM ACCOUNT_TBL_DETAIL WHERE ip='".$ip."'";
$result = mssql_query($sql);
if(!$result) {
die("MSSQL Error");
}
$check = mssql_num_rows($result);
return $check;
}

?>



configs/reg_conf.php
PHP-Code:
<?php
$link = @mssql_connect("PCNAMESQLEXPRESS", "sa", "PASSWORT") or die ("Server is down!");
$db = @mssql_select_db('ACCOUNT_DBF') or die ("Accout table is missing!");
$b = '';
$mail = '';


?>