Are you saying that you utilized one of the options here?
View attachment 92108
When you open an Excel file as Read-Only, and then proceed to make changes (which is totally possible - and the inability to make those edits in cells is
not what Read-Only means)......and then close the file, it will prompt you if you want to Save the file. You can say "yes", but will only be able to save a
copy of the file -
not the file itself
Follow that sequence through entirely and see if it makes more sense?