VB Forum / General / March 2005

You have to ways of doing this, using DirectoryServices or ActiveDs. Here is
a sample code of how you can connect to your active directory using
DirectoryServices

Dim x As Object
       Dim i As Integer
       Dim User As New
System.DirectoryServices.DirectoryEntry("LDAP://xxx.xxx.xxx.255/CN=user,OU=Venezuela,OU=Sales,DC=company, DC=com")
       Dim entry As DirectoryServices.DirectoryEntry
       Dim mySearcher As New
System.DirectoryServices.DirectorySearcher(entry)
       Dim result As System.DirectoryServices.SearchResult

       If TextNombre.Text = "" Then Exit Sub
       i = 0
       mySearcher.Filter = ("(anr=" & TextNombre.Text & ")")
       ListBox1.Items.Clear()

       For Each result In mySearcher.FindAll()
           ListBox1.Items.Add(result.GetDirectoryEntry().Path)
           User = result.GetDirectoryEntry
           Do While i < User.Properties.Count
               x = User.Properties.Item(i)
               i += 1
           Loop
           ListBox1.Items.Add(User.Properties.Item("sn"))  '
User.Properties("HomeNumber")(0))

           'Para que sean realizados los cambios
           'User.CommitChanges()
           '-------------------------------------
       Next

I hope this can give you a hint where to start looking for the
authentication part.
JMP