Imports Microsoft.Office.Interop
 
Public Class Form1
    Dim objOutlook As New Outlook.Application
    Dim mapi As Outlook.NameSpace = objOutlook.GetNamespace("MAPI")
    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button3.Click
        FindFolders(mapi.Folders)
    End Sub
    Private Sub FindFolders(ByVal currentFolder As Outlook.Folders)
        For Each subFolder As Outlook.Folder In currentFolder
            Try
                TreeView1.Nodes.Add(subFolder.Name)
                FindFolders(subFolder.Folders)
            Catch ex As Exception
 
 
 
            End Try
 
        Next
    End Sub
 
 
 
 
End Class