hook_menu/MENU_CALLBACK access denied

Question

I am using hook_menu() to generate a series of MENU_CALLBACKS for processing data at various points in my sites operations. However, while these work for the admin, when trying to access the pages I get the following error message:

You are not authorized to access this page.

I am trying to get this so that the pages can be reached by all users (one is used for submitting a form and processing the results), the other is used for logging outgoing data. The code is as follows:

function modulename_menu() {
  $items = array();
   $items['data/update'] = array(
    'page callback' => 'dataupdate',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
   $items['onthewayout/forward'] = array(
    'page callback' => 'register_click',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  return $items;
}

Answer 1

I tested out the hook_menu in my local. The hook seems fine. Check if you have added an access denied code in the callback function

function commons_menu() {
  $items = array();
   $items['data/update'] = array(
    'page callback' => 'dataupdate',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
   $items['onthewayout/forward'] = array(
    'page callback' => 'register_click',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );
  return $items;
}

function dataupdate() {
  return drupal_set_message("First one is working");
}

function register_click() {
  return drupal_set_message("Second one is also working");
}

This returns a Access Denied to me even if access callback is true.

function register_click() {
  drupal_access_denied();
  exit;
}

Answer 2

You are missing the title key. According to the docs:

"title": Required. The untranslated title of the menu item.