public SimpleMembershipInitializer()
            {
                Database.SetInitializer<UsersContext>( null );

                try
                {
                   using ( var context = new UsersContext() )
                   {
                  if ( !context.Database.Exists() )
                  {
                     // Create the SimpleMembership database without Entity Framework migration schema
                     ((IObjectContextAdapter) context).ObjectContext.CreateDatabase();
                  }
                   }

                   WebSecurity.InitializeDatabaseConnection( "DefaultConnection", "UserProfile", "UserId", "UserName", autoCreateTables: true );
                }
                catch ( Exception ex )
                {
                   throw new InvalidOperationException( "The ASP.NET Simple Membership database could not be initialized. For more information, please see http://go.microsoft.com/fwlink/?LinkId=256588", ex );
                }
            }
        public ActionResult ExternalLoginConfirmation( RegisterExternalLoginModel model, string returnUrl )
        {
            string provider = null;
             string providerUserId = null;

             if ( User.Identity.IsAuthenticated || !OAuthWebSecurity.TryDeserializeProviderUserId( model.ExternalLoginData, out provider, out providerUserId ) )
             {
            return RedirectToAction( "Manage" );
             }

             if ( ModelState.IsValid )
             {
            // Insert a new user into the database
            using ( UsersContext db = new UsersContext() )
            {
               UserProfile user = db.UserProfiles.FirstOrDefault( u => u.UserName.ToLower() == model.UserName.ToLower() );
               // Check if user already exists
               if ( user == null )
               {
                  // Insert name into the profile table
                  db.UserProfiles.Add( new UserProfile { UserName = model.UserName } );
                  db.SaveChanges();

                  OAuthWebSecurity.CreateOrUpdateAccount( provider, providerUserId, model.UserName );
                  OAuthWebSecurity.Login( provider, providerUserId, createPersistentCookie: false );

                  return RedirectToLocal( returnUrl );
               }
               else
               {
                  ModelState.AddModelError( "UserName", "User name already exists. Please enter a different user name." );
               }
            }
             }

             ViewBag.ProviderDisplayName = OAuthWebSecurity.GetOAuthClientData( provider ).DisplayName;
             ViewBag.ReturnUrl = returnUrl;
             return View( model );
        }