救命！！PHP写FTP上传视频在ftp_put()上遇到问题！！

Question

if(@$_POST["action"]=="video_add")
{
    for($i=1;$i<6;$i++)
    {
$video = "video".$i;
$comment = "comment".$i;
$comment = $_POST[$comment];
if(is_uploaded_file($_FILES[$video]['tmp_name']))
        {
              $old_name = $_FILES[$video]["name"];
              $suffix = pathinfo($old_name, PATHINFO_EXTENSION);
     $new_name = time().$i.'.'.$suffix;
            $file_size = $_FILES[$video]["size"]/1024;//文件以k为单位
              if('flv' == $suffix)
            {
                    $source_file = $_FILES[$video]['tmp_name'];
                    $conn_id = ftp_connect($ftp_server);
                    $login_result = ftp_login($conn_id, $ftp_user_name, $ftp_user_pass);
                    $destination_file = $destination.$new_name;                    if ((!$conn_id) || (!$login_result))
                    {
                            echo "FTP connection has failed!";
                            echo "Attempted to connect to $ftp_server for user $ftp_user_name";
                            exit;
                    }
                    else
                    {
                            echo "Connected to $ftp_server, for user $ftp_user_name";
                    }
                    $upload = ftp_put($conn_id, $destination_file, $source_file, FTP_BINARY);
                    if (!$upload)
                    {
                            echo "FTP upload has failed!";//总在报"FTP upload has failed"
                    }
                    else
                    {
                            echo "Uploaded $source_file to $ftp_server as $destination_file";
                            $query = sprintf("insert into video_uploads(video_type_id,who,oldname,newname,comment,uptime,filesize)values
(%d,%d,'%s','%s','%s','%s','%s')",$_POST["video_model"],$_SESSION["system_user"]
,$old_name,$new_name,$comment,date("Y-m-d H:i:s"),$file_size);
    if (!$db->query($query))
    {
echo "fail";
    }
    else
    {
        echo "success";
    }

                    }                    // close the FTP stream
                    ftp_close($conn_id);
                }
                else
                {
error("上传文件格式不正确");
die();
}
}
        else
        {
//do--null;
}
    }
    //go("video_manage.php");
}
出错的地方已经用红色字体标识出来了。
运行结果报FTP upload has failed
服务器端的操作系统是WIN2000。
请各位大大帮帮我吧。谢谢了