how do i help him?
By giving him a crash course in common sense. If he had a combination lock
on something - his safe, his bicycle, whatever - he would make sure he
remembered the combination, wouldn't he? Why should his document password be
any different?
Sorry. He can't. This is an often-asked question to which there is no good
answer. I read in last week's New Scientist that quantum computing is now,
perhaps, less than a decade away so password cracking may become viable in
the future - of course there will be new security techniques by then as
well - but for now it can't be done. He can try giving his credit card
number to one of the many people on the web offering to crack security if he
wants but they don't have a magic bullet or anything.