PHP Code:
<html>
<h3>Testing Stuff</h3>
    <form method = "POST" action ="<?php echo $_SERVER['PHP_SELF'];?>"
    <input type = "hidden" name = "send" value = "1">
    <p>Username:<input type="text" name="UserName" /></p>
    <p>Password:<input type="text" name="Password" /></p>
    <input type="submit" value ="Login" />
</form>
<body background="http://users.pandora.be/creeping_death/Babes/Anna%20Kournikova%2002.jpg">
    <?php
    If ($_POST[send] == "1"){
        $Filename = $_POST[UserName];
            If (file_exists($Filename)){
                $handle = fopen($Filename, "r") or die("Error Reading");
                $contents = @fread($handle,filesize($Filename)) or die("Error2");
                fclose($handle);
                If ($contents == $_POST[Password]){
                    echo "</br>.Logged in";
                }else{
                    echo "Invalid password";
                }

            [B]}else{[/B]
                $handle = fopen($Filename, "w") or die ("Error writing");
                $contents = @fwrite($handle,$_POST[Password];
                fclose($handle);
            }            
?>
</html>
says error on line 25, and i really dont see anything wrong there