Problem : I am very new to the Node.js and I am having few issues. I am using the Node.js 4.10 and Express 2.4.3. While trying to execute my code I am receiving below error : Error: Can't render headers after they are sent to the client. ... , scope: 'offline_access,email,user_about_me,user_activities,manage_pages,publish_stream', failedUri: '/noauth' }) ])); realapp.use(realapp.router); }); . . .