Here's an example of how to do this. You need a form with a timer. Set its interval to something suitable, say 500. When you minimize the window, its task bar icon will flash. When maximized, it won't.
[tt]
Option Explicit
Private Declare Function FlashWindow Lib "user32" (ByVal hwnd As Long, ByVal bInvert As Long) As Long
Private Sub Form_Resize()
Timer1.Enabled = (Me.WindowState = vbMinimized)
End Sub
Private Sub Timer1_Timer()
FlashWindow Me.hwnd, True
End Sub
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