Vertical scroll bar is not shown if the expanded node's child nodes have been collapsed in NodeExpandChanged event previously. The code snippet bellow causes the issue:


void radTreeView1_NodeExpandedChanged(object sender, RadTreeViewEventArgs e)
{
    bool isExpanded = e.Node.Expanded;

    if (!isExpanded)
    {
        foreach (RadTreeNode node in e.Node.Nodes)
        {
            node.Expanded = false;
        }
    }
}