Hola,para detectar la ventana maximizada podes usar la api
IsIconic...algo asi:
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Declare Function IsIconic Lib "user32" (ByVal hwnd As Long) As Long
Private Sub Form_Load()
Timer1.Interval = 100
End Sub
Private Sub Timer1_Timer()
WinWnd = FindWindow("elhwnd", vbNullString)
Me.Caption = IIf(IsIconic(WinWnd) = 0, "Normal", "Minimizado")
End Sub
por su puesto tenes que pasarle el
Hwnd de la ventana padre del messenger..
saludos