检索用户列表时出现Google_ServiceException错误（使用Google API SDK）

我使用以下代码检索与我的Google Apps管理员帐户关联的用户列表 . 使用Google Apps管理员帐户时工作正常，但使用其他Google应用/ Gmail帐户时会出现错误 .

Code:

<?php
require_once 'test_user/src/Google_Client.php';
require_once 'test_user/src/contrib/Google_PlusService.php';
require_once 'test_user/src/contrib/Google_Oauth2Service.php';
require_once 'test_user/src/contrib/Google_DirectoryService.php';

session_start();

$client = new Google_Client();
$client->setApplicationName("ApplicationName");

//*********** Replace with Your API Credentials **************
$client->setClientId('****');
$client->setClientSecret('****');
$client->setRedirectUri('****');
$client->setDeveloperKey('****');
//************************************************************

$client->setScopes(array('https://www.googleapis.com/auth/plus.me     https://www.googleapis.com/auth/userinfo.email     https://www.googleapis.com/auth/admin.directory.user'));
$plus = new Google_PlusService($client);
$oauth2 = new Google_Oauth2Service($client); // Call the OAuth2 class for get email address
$adminService = new Google_DirectoryService($client); // Call directory API

error_reporting(E_ALL);
ini_set('display_errors', 1);
error_reporting(E_ALL ^ E_NOTICE);

if (isset($_REQUEST['logout'])) {
  unset($_SESSION['access_token']);
}

if (isset($_GET['code'])) {
  $client->authenticate();
  $_SESSION['access_token'] = $client->getAccessToken();
  header('Location: http://' . $_SERVER['HTTP_HOST'] . $_SERVER['PHP_SELF']);
}

if (isset($_SESSION['access_token'])) {
  $client->setAccessToken($_SESSION['access_token']);
}

if ($client->getAccessToken())
{
  $user = $oauth2->userinfo->get();
  $me = $plus->people->get('me');
  $email = filter_var($user['email'], FILTER_SANITIZE_EMAIL); // get the USER EMAIL ADDRESS using OAuth2

  $optParams = array('maxResults' => 100);
  $activities = $plus->activities->listActivities('me', 'public', $optParams);
  $users = $adminService->users->get($email);
  //print_r($users);
  //$list_users = $adminService->users->listUsers();
  $adminOptParams = array('customer' => 'my_customer');
  $list_users = $adminService->users->listUsers($adminOptParams);
  print '<h2>Response Result:</h2><pre>' . print_r($list_users, true) . '</pre>';
  $_SESSION['access_token'] = $client->getAccessToken();
}
else
{
  $authUrl = $client->createAuthUrl();
  header("location:$authUrl");
}
?>

Error:

致命错误：未捕获的异常'Google_ServiceException'，显示消息'错误呼叫GET https://www.googleapis.com/admin/directory/v1/users/william.nelson920@gmail.com?key=AIzaSyBp0yBFCCosu113tbNbw7yAIjIt1ndFFIs：（404）资源不找到：userKey'在/var/www/vhosts/vx44.com/httpdocs/test_user/src/io/Google_REST.php:66堆栈跟踪：＃0 /var/www/vhosts/vx44.com/httpdocs/test_user/src /io/Google_REST.php(36）：Google_REST :: decodeHttpResponse（Object（Google_HttpRequest））＃1 /var/www/vhosts/vx44.com/httpdocs/test_user/src/service/Google_ServiceResource.php(186):Google_REST： ：execute（Object（Google_HttpRequest））＃2 /var/www/vhosts/vx44.com/httpdocs/test_user/src/contrib/Google_DirectoryService.php(653):Google_ServiceResource - > __ call（'get'，Array）＃3 / var / www / vhosts / vx44.com / httpdocs / test_user / test_user.php（54）：/ var / www / vhosts / vx44中抛出了Google_UsersServiceResource-> get（'william.nelson9 ...'）＃4 第66行的.com / httpdocs / test_user / src / io / Google_REST.php