treeview没找到这个目录

点击我的电脑或者+号时，会弹出没找到目录

怎么用分支解决，如果这个地方是我的电脑该怎么做，不是该怎么做。

下面是代码

TreeNode CountNode1 = new TreeNode("我的电脑");

                treeView_File.Nodes.Add(CountNode1);
        foreach (string DrvName in Directory.GetLogicalDrives())
        {
            TreeNode aNode = new TreeNode(DrvName);
            aNode.Tag = DrvName;
            CountNode1.Nodes.Add(aNode);
        }
        foreach (string DrvName in Directory.GetLogicalDrives())
        {

            ListViewItem ItemList = new ListViewItem(DrvName);
            listView_File.Items.Add(ItemList);
        }
        treeView_File.ExpandAll();
    }

    private void treeView_File_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e)
    {
        if(e.Node.Nodes.Count==0)
        {
            if (e.Node.Parent == null)
            {
                foreach (string DrvName in Directory.GetLogicalDrives())
                {
                    TreeNode aNode = new TreeNode(DrvName);
                    aNode.Tag = DrvName;
                    e.Node.Nodes.Add(aNode);
                }
            }
            else
            {
                foreach (string DirName in Directory.GetDirectories((string)e.Node.Tag))
                {
                    TreeNode aNode = new TreeNode(DirName);
                    aNode.Tag = DirName;
                    e.Node.Nodes.Add(aNode);
                }
            }
        }

        ListView_Show(e.Node.Text);
    }

    private void listView_File_MouseDoubleClick(object sender, MouseEventArgs e)
    {

        ListView_Show(listView_File.FocusedItem.Text);
    }

    private void ListView_Show(string DirText)
    {
        listView_File.Clear();
        foreach (string DirName in Directory.GetDirectories(DirText))
        {
            ListViewItem ItemList = new ListViewItem(DirName);
            listView_File.Items.Add(ItemList);
        }
        foreach (string FileName in Directory.GetFiles(DirText))
        {
            ListViewItem ItemList = new ListViewItem(FileName);
            listView_File.Items.Add(ItemList);
        }
    }
}

}

f盘是不是光驱、网络驱动器或者没有权限
https://bbs.csdn.net/topics/380239317
代码下载 http://download.csdn.net/detail/caozhy/4169965 。