title: IAppbuilder does not contain a definition for "usefacebookauthentication" in asp.net identity for external login
body: <p>I want to activate the external login (facebook) in asp.net mvc5 but i don't know what to do with this error. Please help</p>
  
  <p><img src="https://i.stack.imgur.com/yVnee.png" alt="Click Here for error photo"></p>