There's just one word to describe your friend's assertion: Poppycock! No law says you have to cash a check within 30 days. Generally, banks and credit unions do not have to honor checks that are more than six months old. But most banks will go ahead and honor old checks anyway.

Tell your friend, "Nice try," but he can't get rid of his debt to you on this technicality. Of course, maybe when he says it's "too late" to cash the check, he means that there is no money in the bank. Don't waste any time in finding out.