RadControls for ASP.NET AJAX upgrade - 'IsCallBack' and 'AutoPostBack' properties not found for Telerik.Web.UI classes

Question

Distinct error:

'Telerik.Web.UI.RadTreeView' does not contain a definition for 'IsCallBack' and no extension method 'IsCallBack' accepting a first argument of type 'Telerik.Web.UI.RadTreeView' could be found (are you missing a using directive or an assembly reference?)

Code:

  protected void Page_Load(object sender, EventArgs e)
  {
     if (!this.IsPostBack && !this.sectionTree.IsCallBack)
     {
        //populate the first level of tree nodes
        foreach (SiteSection section in SiteSectionCollection.GetRootSections())
        {
           RadTreeNode node = new RadTreeNode(section.Name, section.AssetId.ToString());
           node.ExpandMode = ExpandMode.ServerSideCallBack;
           this.sectionTree.Nodes.Add(node);
        }
     }
  }

Distinct error:

'Telerik.Web.UI.RadComboBox' does not contain a definition for 'IsCallBack' and no extension method 'IsCallBack' accepting a first argument of type 'Telerik.Web.UI.RadComboBox' could be found (are you missing a using directive or an assembly reference?)

Code:

  protected void Page_Load(object sender, EventArgs e)
  {
     if (!this.IsPostBack && !this.sectionTree.IsCallBack)
     {
        //populate the first level of tree nodes
        foreach (SiteSection section in SiteSectionCollection.GetRootSections())
        {
           RadTreeNode node = new RadTreeNode(section.Name, section.AssetId.ToString());
           node.ExpandMode = ExpandMode.ServerSideCallBack;
           this.sectionTree.Nodes.Add(node);
        }
     }
  }

Distinct error:

'Telerik.Web.UI.RadTreeView' does not contain a definition for 'AutoPostBack' and no extension method 'AutoPostBack' accepting a first argument of type 'Telerik.Web.UI.RadTreeView' could be found (are you missing a using directive or an assembly reference?)

Code:

  protected override void OnPreRender(EventArgs e)
  {
     base.OnPreRender(e);

     if (rtvTreeView != null)
        rtvTreeView.AutoPostBack = NodeClick != null;
     cmbCombobox.AutoPostBack = ItemsRequested != null;
  }

Background:

When upgrading from "RadControls for ASP.NET" to "RadControls for ASP.NET AJAX", I ran into several issues. The web.config file was converted by the Upgrade Wizard. I started with 233 .NET compilation errors (28 distinct errors) which I quickly resolved, but I still have 36 errors (13 distinct issues) left from drastic API changes that I still haven't resolved. I will post these 13 errors as questions on stack overflow to save me some time. While I'm waiting I will try downloading their control demos and understand how the controls work for their newest release and answer them myself for those others haven't answered.

Answer 1

Errors #1 and #2:

protected void Page_Load(object sender, EventArgs e)
  {
     if (!this.IsPostBack && !this.Page.IsCallBack)
     {
        //populate the first level of tree nodes
        foreach (SiteSection section in SiteSectionCollection.GetRootSections())
        {
           RadTreeNode node = new RadTreeNode(section.Name, section.AssetId.ToString());
           node.ExpandMode = ExpandMode.ServerSideCallBack;
           this.sectionTree.Nodes.Add(node);
        }
     }
  }