[Marco van Herwaarden]

 <form name="form1" method="post" action="test.php?do=save">

Should be:

 <form name="form1" method="post" action="test.php">
	<input type="hidden" name="do" value="save" />
 

Change:

PHP Code:

if ($_REQUEST['do'] == 'save') 
{ 
$vbulletin->db->query_write("INSERT INTO `Links` (`id`, `Name`, `url`, `description`) VALUES ('10', '$name', '$url', '$description');"); 
} 


To:

PHP Code:

if ($_REQUEST['do'] == 'save') 
{
    $vbulletin->input->clean_array_gpc('p', array(
        'name'                => TYPE_STR,
        'url'                    => TYPE_STR,
        'description'    => TYPE_STR
        ));
 
    $vbulletin->db->query_write("INSERT INTO `Links` (`id`, `Name`, `url`, `description`) 
            VALUES ('10'
            ,    '" . $vbulletin->db->escape_string($vbulletin->GPC['name']) . "'
            ,    '" . $vbulletin->db->escape_string($vbulletin->GPC['url']) . "'
            ,    '" . $vbulletin->db->escape_string($vbulletin->GPC['description']) . "'
            );"); 
}