public bool LogOff()
 {
     CurrentUserManager.LogOff(_sessionManager);
     _authenticationManager.SignOut(DefaultAuthenticationTypes.ApplicationCookie,
                                    OAuthDefaults.AuthenticationType,
                                    DefaultAuthenticationTypes.ExternalCookie,
                                    DefaultAuthenticationTypes.ExternalBearer,
                                    DefaultAuthenticationTypes.TwoFactorCookie,
                                    DefaultAuthenticationTypes.TwoFactorRememberBrowserCookie);
     return(true);
 }