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asp telerik treeView throws an exception when trying to renderControl
try{
   StringWriter writer = new StringWriter();
   HtmlTextWriter tOut = new HtmlTextWriter(writer);
   ddFieldFilter.RenderControl(tOut);  //This doesnt error.
   tvFields = new RadTreeView();
   tvFields.NodeExpand += new RadTreeViewEventHandler(tvFields_NodeExpand);
   tvFields.NodeClick += new RadTreeViewEventHandler(tvFields_NodeClick);
   startTree();
   tvFields.RenderControl(tOut);  //Errors here.
   String context = writer.toString();
}catch(Exception e){
   throw new Exception("Error Loading Page: " + e.Message);
}