To reproduce: Add some nodes to a tree, and then clear them and move them to another tree. The inner nodes expand/collapse does not work correctly: void radButton1_Click(object sender, EventArgs e) { tree1.Nodes.Clear(); tree2.Nodes.AddRange(nodes); } RadTreeView tree1 = new RadTreeView(); RadTreeView tree2 = new RadTreeView(); List<RadTreeNode> nodes = new List<RadTreeNode>(); private void Populate(RadTreeView tree) { RadTreeNode n11 = new RadTreeNode("11"); RadTreeNode n12 = new RadTreeNode("12"); RadTreeNode n13 = new RadTreeNode("13"); RadTreeNode n14 = new RadTreeNode("14"); nodes.Add(n11); nodes.Add(n12); nodes.Add(n13); nodes.Add(n14); RadTreeNode n21 = new RadTreeNode("21"); RadTreeNode n22 = new RadTreeNode("22"); RadTreeNode n23 = new RadTreeNode("23"); RadTreeNode n24 = new RadTreeNode("24"); n11.Nodes.Add(n21); n11.Nodes.Add(n22); n11.Nodes.Add(n23); n11.Nodes.Add(n24); RadTreeNode n31 = new RadTreeNode("31"); RadTreeNode n32 = new RadTreeNode("32"); RadTreeNode n33 = new RadTreeNode("33"); RadTreeNode n34 = new RadTreeNode("34"); n21.Nodes.Add(n31); n21.Nodes.Add(n32); n21.Nodes.Add(n33); n21.Nodes.Add(n34); tree.Nodes.AddRange(nodes); } 1. Run 2. Expand all nodes in tree1 3. Select node 23 4. Press button move right 5. Click at "plus" at node 21. -> expand collapse does not work correctly Workaround - instead of calling the Clear method of the Nodes collection, remove them manually: while (tree1.Nodes.Count > 0) { tree1.Nodes.RemoveAt(0); }