Hi, Following the information in Umbraco Documentation i wrote the following code OnApplicationStarted event to use IoC and AutoFac.

        //register all MVC controllers and API controllers in the
        //current assembly in the container.
        var builder = new ContainerBuilder();

        //Register the UmbracoContext as a factory since the below controllers require this in their ctor
        builder.Register(c => UmbracoContext.Current).AsSelf();
        builder.RegisterInstance(ApplicationContext.Current).AsSelf();
        builder.RegisterInstance(new UmbracoHelper(UmbracoContext.Current)).AsSelf();

        builder.RegisterControllers(Assembly.GetExecutingAssembly());
        builder.RegisterApiControllers(Assembly.GetExecutingAssembly());
        builder.RegisterAssemblyTypes(Assembly.GetExecutingAssembly()).AsImplementedInterfaces().InstancePerLifetimeScope();

        // register Umbraco MVC + web API controllers used by the admin site
        builder.RegisterControllers(typeof(UmbracoApplication).Assembly);
        builder.RegisterApiControllers(typeof(UmbracoApplication).Assembly);

        // add custom class to the container as Transient instance
        RegisterTypes(builder);

        var container = builder.Build();

        //setup the webapi dependency resolver to use autofac
        var resolver = new AutofacWebApiDependencyResolver(container);
        GlobalConfiguration.Configuration.DependencyResolver = resolver;

        //setup the mvc dependency resolver to user autofac
        DependencyResolver.SetResolver(new AutofacDependencyResolver(container));

Unfortunately, i am still getting YSOD errors in backend when i click on CONTENT menu. Also the umbraco menu items on the left side are not loaded and finally when i execute code to add content from code behind the content is not added.

The errors i am getting when i click in Content are the following:

System.AggregateException: One or more errors occurred.

at System.Threading.Tasks.Task1.GetResultCore(Boolean waitCompletionNotification) at Umbraco.Web.Editors.SectionController.GetSections() at lambda_method(Closure , Object , Object[] ) at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.<>c__DisplayClass10.<GetExecutor>b__9(Object instance, Object[] methodParameters) at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.Execute(Object instance, Object[] arguments) at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ExecuteAsync(HttpControllerContext controllerContext, IDictionary2 arguments, CancellationToken cancellationToken) --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Web.Http.Controllers.ApiControllerActionInvoker.

Inner Exception

System.NullReferenceException: Object reference not set to an instance of an object.

at Umbraco.Web.Trees.ApplicationTreeExtensions.