Fatal error: Uncaught exception 'Google_Service_Exception' with message 'Error calling GET https://www.googleapis.com/oauth2/v2/userinfo: (401) Request is missing required authentication credential. Expected OAuth 2 access token, login cookie or other valid authentication credential. See https://developers.google.com/identity/sign-in/web/devconsole-project.' in C:\xampp\htdocs\balancebiz\google_login\libraries\Google\Http\REST.php:110 Stack trace: #0 C:\xampp\htdocs\balancebiz\google_login\libraries\Google\Http\REST.php(62): Google_Http_REST::decodeHttpResponse(Object(Google_Http_Request), Object(Google_Client)) #1 [internal function]: Google_Http_REST::doExecute(Object(Google_Client), Object(Google_Http_Request)) #2 C:\xampp\htdocs\balancebiz\google_login\libraries\Google\Task\Runner.php(174): call_user_func_array(Array, Array) #3 C:\xampp\htdocs\balancebiz\google_login\libraries\Google\Http\REST.php(46): Google_Task_Runner->run() #4 C:\xampp\htdocs\balancebiz\google_login\libraries\Google\Client.php(593): Google_Http_RE in C:\xampp\htdocs\balancebiz\google_login\libraries\Google\Http\REST.php on line 110