HTTP/1.1 500 Notice: "ob_flush() [<a href='ref.outcontrol'>ref.outcontrol</a>]: failed to flush buffer. No buffer to flush." at line 170 of G:\localhost\4ddynamics.eu\securefiles\code\SecureFileController.php

<?php
class TrackDownload extends DataObjectDecorator {
function extraStatics() {
      return array(
         'many_many' => array(
            'Members' => 'Member' // Downloaders
         )
      );
// Return an array containing keys 'db', 'has_one', 'many_many', 'belongs_many_many',
}

   public function onAccessGranted() {
      $member = Member::currentUser();
      $this->owner->Members()->add($member);
      $this->owner->Members()->write();
      //Debug::Show("Access Granted");
   }

   public function onAccessDenied() {
//      Debug::Show("Access Denied");
//      exit();
   }

   public function summaryFields() {
      return array(
         'Members' => 'User'
      );
   }

   public function getCMSFields() {
      $fields = parent::getCMSFields();
   $this->extend('updateCMSFields', $fields);
   return $fields;
   }

   public function updateCMSFields(FieldSet $fields) {
   // DataObject::get("Product", "", "Title ASC")->toDropdownMap()
//      $fields->addFieldToTab("Root.Downloaders", new CheckboxSetField('Members','Downloaders', $this->Members));
   }
}

<?php
class User extends DataObjectDecorator {
function extraStatics() {
      return array(
         'db' => array(
            'Company' => 'Varchar(255)',
            'Country' => 'Varchar(255)',
            'Marketing' => 'Boolean',
         ),
         'many_many' => array(
            'Products' => 'Product',
         ),
         'belongs_many_many' => array(
            'Downloaded' => 'File'
         )
      );
// Return an array containing keys 'db', 'has_one', 'many_many', 'belongs_many_many',
}

function somethingElse() {
// You can add any other methods you like, which you can call directly on the member object.
}

   public function getCMSFields() {
      $fields = parent::getCMSFields();
   $this->extend('updateCMSFields', $fields);
   return $fields;
   }

   public function updateCMSFields(FieldSet $fields) {
$fields->addFieldToTab("Root.Main", new TextField('Company', 'Company'), "MemberUserDetailsHeader");
$fields->addFieldToTab("Root.Main", new TextField('Country', 'Country'), "MemberUserDetailsHeader");

      $fields->addFieldToTab("Root.Products", new CheckboxSetField('Products','Interested in products (check all that apply)', DataObject::get("Product", "", "Title ASC")->toDropdownMap()));
   }
}

DataObject::add_extension('Member', 'User');
DataObject::add_extension('File', 'TrackDownload');