In my version (Windows 10 Pro, 64 bit if it matters) the "Save As" dialog has an "Encoding" drop-down which includes "UTF-8" and "UTF-8 with BOM". I'm making a (perhaps unwarranted) assumption that the former does not include a BOM. I would try first with a new, empty file: it's conceivable that it won't _remove_ a BOM that's already there, although I suspect it might.