How to set up api vk authorization on the site?

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On my site musicvkontakte.ru , you need to correctly configure authorization. Now when you log in, it just opens the site in a new window. I think the problem is in this file musicvkontakte.ru/js/common_functions.js
It should be like here vkmuzic.com, what is the problem and describe the solution in detail, I will be grateful