Attachment help

[da_judge]

Im workin on something to do with downloads... Im having trouble with it grabbing attachments..

Im using file system not db... this is the code im using... all files are 0 bytes

//Getting attachment
if ($vbulletin->input->clean_gpc('g','id',TYPE_UNIT))
{
//attachment id
$id=intval($vbulletin->GPC['id']);
//select the content from the table
$get_zip=$db->query_read("SELECT *FROM ".TABLE_PREFIX."attachment where attachmentid=$id");
// print the file
while($_zip=$db->fetch_array($get_zip))
{

Any ideas where im going wrong

Cheers