Scan folders and subfolders with treeview all most working need help please

Imports System.IO
Public Class form1

    Private Sub form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        tv1.Nodes.Clear()
        For Each drv As DriveInfo In My.Computer.FileSystem.Drives
            If drv.IsReady Then Call LoadFolderTree(drv.Name)
        Next
        tv1.Nodes(0).Expand()
        On Error Resume Next
        tv1.Nodes(1).Expand()
    End Sub

    Public Sub LoadFolderTree(ByVal path As String)
        Dim basenode As System.Windows.Forms.TreeNode, volbl As String, drvltr As String = path
        If IO.Directory.Exists(path) Then
            If path.Length <= 3 Then
       volbl = My.Computer.FileSystem.GetDriveInfo(path).VolumeLabel
       If Len(drvltr) = 3 Then drvltr = Mid(drvltr, 1, 2)
       basenode = tv1.Nodes.Add(String.Format("{0} ({1})", volbl, drvltr))
            Else
            basenode = tv1.Nodes.Add(My.Computer.FileSystem.GetName(path))
            End If
            basenode.Tag = path
            LoadDir(path, basenode)
        Else
            Throw New DirectoryNotFoundException()
        End If
    End Sub

    Private Sub tv1_AfterSelect(ByVal sender As System.Object, ByVal e As System.Windows.Forms.TreeViewEventArgs) Handles tv1.AfterSelect
        lblMessage.Text = tv1.SelectedNode.Tag
    End Sub

    Private Sub tv1_KeyDown(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles tv1.KeyDown
        If e.KeyCode = Keys.Enter Then
            Dim snd As TreeNode = tv1.SelectedNode
            On Error Resume Next
            tv1.CollapseAll()
            snd.Expand()
            tv1.SelectedNode = snd
        End If
    End Sub

Private Sub tv1_AfterExpand(ByVal sender As System.Object, ByVal e As System.Windows.Forms.TreeViewEventArgs) Handles tv1.AfterExpand
        Dim n As System.Windows.Forms.TreeNode
        For Each n In e.Node.Nodes
            LoadDir(n.Tag, n)
        Next
    End Sub
Public Sub LoadDir(ByVal DirPath As String, ByVal Node As Windows.Forms.TreeNode)
        On Error Resume Next
        Dim Dir As String, DirName As String, Index As Integer
        If Node.Nodes.Count = 0 Then
        For Each Dir In My.Computer.FileSystem.GetDirectories(DirPath)
        Index = Dir.LastIndexOf("\") : DirName = Dir.Substring(Index + 1, Dir.Length - Index - 1)
       If fncAddThisDir(DirName) Then Node.Nodes.Add(DirName) : Node.LastNode.Tag = Dir : Node.LastNode.ImageIndex = 0
            Next
        End If
    End Sub

    Function fncAddThisDir(ByVal dirname As String) As Boolean
        If Mid(LCase(dirname), 1, 7) = "program" Then dirname = "Program"
        Select Case LCase(dirname)
            Case ""
            Case "$avg","$recycle.bin"
            Case "recycler", ".wd_tv"
            Case Else : fncAddThisDir = True
        End Select
    End Function

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        LookAtDir(lblMessage.Text.ToString)

    End Sub
    Private Sub LookAtDir(ByVal path As String)
        Try
            For Each dir As String In Directory.GetDirectories(path)
                LookAtDir(dir)
            Next
            Do something with the directory.
        Catch ex As UnauthorizedAccessException
        End Try
    End Sub
End Class