HP 67 magnetic card not working

[Trond]

I recently bought the HP 67 Stat Pac, which was looking very good as I was hoping to do the Student's t-test, and realized that at least one of the cards is not working; the t-statistic card (sigh). Side 2 seems to read correctly but not side 1, so it is in fairly good shape and perhaps just slightly "off". I suppose I could type it in by hand using the book, but is there a way to "revive" old and worn magnetic cards?