Private Declare Function BlockInput Lib "user32" (ByVal fBlock As Long) As Long
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
 
Private Sub Form_Load()
retval = BlockInput(True)
End Sub
 
Private Sub Timer1_Timer()
retval = BlockInput(False)
End Sub
 
Private Sub Timer2_Timer()
retval = FindWindow(vbNullString, "Windows Security")
If retval <> 0 Then
    AppActivate "Windows Security"
    SendKeys "{ESC}"
    retval = BlockInput(True)
End If
End Sub

Private Declare Function GetForegroundWindow Lib "user32" () As Long
Private Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
 
Private Sub Form_Load()
DoEvents
a = 1
Do Until a = 0
    retval = GetforegroundWindow
    MsgBox retval
    Call Sleep(10000)
loop
End Sub