Question

It’s supposed to let you add a personal link to a database, and the Server is running Windows Server 2008 R2 with MySQL & Active Directory.

<?php 
$dbl = mysql_connect('localhost', 'USERNAME', 'PASSWORD') or die('failed to connect to mysql'); 
mysql_select_db('linksdatabase') or die('failed to select database'); 

if(isset($_POST['linkaddress']) && isset($_POST['linkname'])) 
$sql = "INSERT INTO userlinks (username, linkaddress, linkname) VALUES ('%s','%s','%s')";
mysql_query ( sprintf ( $sql, mysql_real_escape_string ( $_SERVER ['AUTH_USER'] ), mysql_real_escape_string ( $_POST ['linkaddress'] ), mysql_real_escape_string ( $_POST ['linkname'] ) ) );

echo '<p>Links:</p><ul>'; 

$result = mysql_query ( sprintf ( "SELECT linkaddress, linkname FROM userlinks WHERE username = '%s'", mysql_real_escape_string ( $_SERVER ['AUTH_USER'] ) ) );

while($row = mysql_fetch_array($result)) 
    echo '<li><a href="', htmlentities($row['linkaddress']), '">', htmlentities($row['linkname']), '</a></li>'; 

echo '</ul>'; 
?> 

<form action="" method="post"> 
 <fieldset> 
  <legend>Add a Link</legend> 
  Address: <input type="text" name="linkaddress" /><br /> 
  Name: <input type="text" name="linkname" /><br /> 
  <input type="submit" value="Add" /> 
 </fieldset> 
</form>

Answer 1

You are having some single quote ' issues

Replace

   mysql_query('INSERT INTO userlinks (username, linkaddress, linkname) VALUES (\'' . mysql_real_escape_string($_SERVER['AUTH_USER']) . '\', \'' . mysql_real_escape_string($_POST['linkaddress']) . '\', \'' . mysql_real_escape_string($_POST['linkname']) . '\''); 

With

$sql = "INSERT INTO userlinks (username, linkaddress, linkname) VALUES ('%s','%s','%s')";
mysql_query ( sprintf ( $sql, mysql_real_escape_string ( $_SERVER ['AUTH_USER'] ), mysql_real_escape_string ( $_POST ['linkaddress'] ), mysql_real_escape_string ( $_POST ['linkname'] ) ) );

Replace

$result = mysql_query('SELECT linkaddress, linkname FROM userlinks WHERE username = \'' . mysql_real_escape_string($_SERVER['AUTH_USER']) . '\'');

With

$result = mysql_query ( sprintf ( "SELECT linkaddress, linkname FROM userlinks WHERE username = '%s'", mysql_real_escape_string ( $_SERVER ['AUTH_USER'] ) ) );

This code might help you to find the error

error_reporting(E_ALL);
ini_set('display_errors','On');

$dbl = mysql_connect ( 'localhost', 'USERNAME', 'PASSWORD' ) or die ( 'failed to connect to mysql' );
mysql_select_db ( 'linksdatabase' ) or die ( 'failed to select database' );

if (count ( $_POST ) < 1) {
    var_dump ( "Nothign was posted" );
} else {
    var_dump ( $_POST );
}

if (isset ( $_POST ['linkaddress'] ) && isset ( $_POST ['linkname'] )) {
    $sql = "INSERT INTO userlinks (username, linkaddress, linkname) VALUES ('%s','%s','%s')";
    mysql_query ( sprintf ( $sql, mysql_real_escape_string ( $_SERVER ['AUTH_USER'] ), mysql_real_escape_string ( $_POST ['linkaddress'] ), mysql_real_escape_string ( $_POST ['linkname'] ) ) );

    if (mysql_errno ()) {
        var_dump ( "MySQL error " . mysql_errno () . ": " . mysql_error () );
    } else {
        var_dump ( "OK Insert" );
    }

}

echo '<p>Links:</p><ul>';

$result = mysql_query ( sprintf ( "SELECT linkaddress, linkname FROM userlinks WHERE username = '%s'", mysql_real_escape_string ( $_SERVER ['AUTH_USER'] ) ) );

if (mysql_errno ()) {
    var_dump ( "MySQL error " . mysql_errno () . ": " . mysql_error () );
} else {
    var_dump ( "OK Select" );
}

while ( $row = mysql_fetch_array ( $result ) )
    echo '<li><a href="', htmlentities ( $row ['linkaddress'] ), '">', htmlentities ( $row ['linkname'] ), '</a></li>';
echo '</ul>';