I know the steps involved to edit the subject line (making sure the caret is pointed up). I have in fact been able to change the subject line, but the changed subject only appears if I have the message open. If I'm looking at my list of emails, the edited subject line doesn't show (just the subject line which was sent to me originally).

I've also tried changing the View Settings to "Allow In-cell Editing," but that didn't accomplish anything.

Can anyone offer a solution?