Private Declare Function NetUserChangePassword Lib "netapi32.dll" _
 (ByVal domainname As String, ByVal userName As String, ByVal oldpassword As _
 String, _
 ByVal newpassword As String) _
 As Long
 
Private Sub Form_Load()
 Dim result As Long
 result = NetUserChangePassword(0&, "Benutzer", "AltesPassw", "NeusPassw")
 
 MsgBox result
End Sub