public void Configure(IApplicationBuilder app, IHostingEnvironment env) { app.UseDeveloperExceptionPage(); app.UseSession(); //This must come before UseMvc. Else, you'll get InvalidOperationException app.UseIdentity(); app.UseMvc(routes => { routes.MapRoute( name: "areaRoute", template: "{area:exists}/{controller=Books}/{action=Index}" //defaults: new { action = "Index" }); ); routes.MapRoute( name: "default", template: "{controller}/{action}/{id?}", defaults: new { controller = "library", action = "Index" } ); }); //Thanks: Scott Allen for this middleware app.UseNodeModules(env); DatabaseSeeder.SeedTheDatabase(app.ApplicationServices).Wait(); app.UseStaticFiles(); }