private void openBtn_Click(object sender, EventArgs e)
        {
            ofdEdb.FileName = WLMRegUtil.GetMailMSMessageStore();
            if (ofdEdb.ShowDialog(this) == DialogResult.OK)
            {
                using (new AH())
                    using (var es = new ES())
                    {
                        es.Open(ofdEdb.FileName);
                        folders = es.ReadEntireTable <Folder>("Folders").ToArray();
                    }

                folderTree.Nodes.Clear();
                Build(folderTree.Nodes, 0, folders, Path.GetDirectoryName(ofdEdb.FileName), CreateNumTag);
            }
        }