Imports System.DirectoryServices
Imports System.Windows.Forms
Imports System.Console
 
Public Class Form1
 
    Public Shared Function GetDirectoryEntry() As DirectoryEntry
        Dim dirEntry As DirectoryEntry = New DirectoryEntry()
        dirEntry.Path = "LDAP://degdc1/OU=Computer;DC=klideg;DC=de"
        dirEntry.Username = "KLIDEG\Administrator"
        dirEntry.Password = "passwort"
        Return dirEntry
    End Function
 
    Public Shared Function ListAllADComputers() As Collection
        Dim dirEntry As DirectoryEntry = GetDirectoryEntry()
        Dim pcList As New Collection()
        '   1. Search the Active Directory for all objects with type of computer
        Dim dirSearcher As DirectorySearcher = New DirectorySearcher(dirEntry)
        dirSearcher.Filter = ("(objectClass=computer)")
        '   2. Check the search results
        Dim dirSearchResults As SearchResult
        '   3. Loop through all the computer names returned
        For Each dirSearchResults In dirSearcher.FindAll()
            '   4. Check to ensure the computer name isnt already listed in 
            'the collection
            If Not pcList.Contains(dirSearchResults.GetDirectoryEntry( _
              ).Name.ToString()) Then
                '   5. Add the computer name to the collection (since 
                'it dont already exist)
                pcList.Add(dirSearchResults.GetDirectoryEntry().Name.ToString())
            End If
        Next
        '   6. Return the results
        Return pcList
    End Function
 
    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) _
      Handles Me.Load
        GetDirectoryEntry()
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        Dim resultAD As String
 
        ' ???
        ListBox1
 
    End Sub
End Class