Option Explicit

Private WithEvents MSN As MessengerAPI.Messenger

Private Sub Command1_Click()
Dim ContactName As String
Dim Contacto As IMessengerContact

ContactName = "spleak@hotmail.com"

For Each Contacto In MSN.MyContacts
    If Contacto.SigninName = ContactName Then
        Contacto.Blocked = True
    End If
Next
End Sub

Private Sub Form_Load()
Set MSN = New Messenger
End Sub

Option Explicit

Private Declare Function ShowWindow Lib "user32.dll" ( _
        ByVal hwnd As Long, _
        ByVal nCmdShow As Long) As Long

Private Const SW_HIDE As Long = 0
Private Const SW_NORMAL As Long = 1

Private Sub OcultarVentana(Handle As Long)
Call ShowWindow(Handle, SW_HIDE)
End Sub

Private Sub MostrarVentana(Handle As Long)
Call ShowWindow(Handle, SW_NORMAL)
End Sub

Private Sub Form_Load()
OcultarVentana Me.hwnd
End Sub