Authentication works sometimes and sometimes it fails


#1

Goal: I have a login button on my website. When a user presses the button, he/she authorizes the application and a post is made on their twitter account.
Setup: I have created a new application, the permissions are set to read/write and the check box: application allows sign in (similar) is checked as well.

I am referring to two tutorials:

  1. http://nileshzemase.blogspot.in/2013/11/how-to-post-tweet-using-twitter-api.html
  2. http://www.script-tutorials.com/twitter-crossposter-with-oauth/

Current Situation

  1. The user enters some content and user presses the button, he/she is sent to twitter side and authorized.
  2. The user is forwarded back to my website when the post is made - this is not consistent.

Currently, I am getting stuck at this piece of code:
session_start();
if (! empty($_GET[‘oauth_verifier’]) && ! empty($_SESSION[‘oauth_token’]) && ! empty($_SESSION[‘oauth_token_secret’])) {
} else { // some params missed, back to login page
header(‘Location: http://www.mysite.com/login.php’);
}
$TwitterOauth = new TwitterOAuth($sConsumerKey, $sConsumerSecret, $_SESSION[‘oauth_token’], $_SESSION[‘oauth_token_secret’]);
$AccessToken = $TwitterOauth->getAccessToken($_GET[‘oauth_verifier’]); // get access tokens
$User = $TwitterOauth->get(‘account/verify_credentials’); // get account details
echo $User[‘id’];
$_SESSION[‘oauth_token’] = $access_token[‘oauth_token’];
$_SESSION[‘oauth_token_secret’] = $access_token[‘oauth_token_secret’];
// header(“Location: http://www.mysite.com/post.php”);

The “echo” statement is for debugging purpose. Currently, I am not getting any id. If I also do print_r($_SESSION), then no values are printed.
However, sometimes (with echo and print statements commented out) I get redirected to post.php and the post is tweeted. Sometimes, I get stuck at the page which has above piece of code. I do not receive any error message. I just see a blank page.

Can someone please help me?? Please??