Windows non si spegne se è attivo un programma .net

  'gestione chiusura sistema operativo:
    'intercetta i messaggi eventi di windows e verifica la chiusura
    Private Shared WM_QUERYENDSESSION As Integer = &H11
    Private Shared systemShutdown As Boolean = False

    Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)

        If m.Msg = WM_QUERYENDSESSION Then
            systemShutdown = True
            Me.Close()
        End If
        ' If this is WM_QUERYENDSESSION, the closing event should be fired in the base WndProc
        MyBase.WndProc(m)

    End Sub