I have tried and can't figured out what is the problem is about. After successful authorization my forum redirects to this link :

http://www.ictbd.info/index.php?u=/uni_login/login/Google

Then I am getting a message like:

User profile request failed. Most likely the user is not connected to the provider and he should to authenticate again.

and, on the next line it shows an error message like:

Fatal error: Call to a member function logout() on null in : 
....... /sites/default/plugins/uni_login/uni_login.php on line 174

Please help to solve the problem. If you need more information please ask.
Thanks in advance.