Description : My home-made marmalade won't set. Can I open the jars and add pectin?
Last Answer : I have in the past made a jelly that didn't gel. We re-opened the jars and re-boiled, as you describe. Of course, we also re-sterilized the jars and everything, and just started fresh. We didn't add ... could do it that way as well. In short, yes, your idea should work, or at least won't hurt.