В VBS вроде так:
Как можно в Autoit сделать.
Код:
Sub test()
Dim objXL
Dim Secur
Set objXL = CreateObject("Excel.Application")
objXL.Visible = TRUE
secur = objXL.AutomationSecurity
objXL.AutomationSecurity = 1
objXL.Workbooks.Open replace(Wscript.ScriptFullName,".vbs",".xlsb"),,,,"4321"
objXL.AutomationSecurity = secur
End Sub