If you are trying to make a Hidden in excel you must do as you describe set the visible property to false. SInce this properly is saved with the file, I assume you are making it visible after you open it so you can work with it.
If you mean the “hidden attribute” in windows you can use something like this line in code (after you have saved and closed the file):
SetAttr "h:hideme.xls", vbHidden
To set the properties of the file to hidden
Steve
