A little more text explaining where you get stuck might help (tell us which wires you can figure out, and which ones you can't).
Anyway, if you never want this VI to give you a dialog, simply wire a FALSE constant to 'Advisory dialog?'.
If you wire TRUE to it, or leave it unwired, LV will give you a dialog if you want to open a file (specified by 'file path') and it does NOT exist, or if you want to create/replace a file and it DOES exist.
The file you actually want to open/create/replace is specified by the 'file path' input. If this is empty, LV will also show a dialog.
I am not sure what happens if you leave the 'file path' empty, and wire FALSE to 'Advisory dialog?', but that's easy to test.
In your case, to avoid a dialog always, make sure the 'file path' is
never empty and the 'Advisory dialog?' is wired to a FALSE constant.
