Problem using roles with MVC5

I have a new MVC5 site, I choose Indervidual User acocunts for authentication. 

What i want to do is put users in roles but when trying I fo8und i have to enable rolemanager in the web.config file. But when i do, i get errors in the site when using My.User.IsInRole("Admin") , error says can not connect to sql. 

Does someone have a same of how to enable roles?

thanks