Word: how do I update cross-references in footnotes?

i’m using Word 2007. It says that there’s a way to update cross-references in footnotes (e.g., “25. See Smith, cited at footnote 15, above.”)

However, I can’t find out to do it. When I try the so-called Help function, it is particularly unhelpful.

Gaah!

To my knowledge, if you used the citation feature when you wrote the cross-reference in note 25, then the cross reference will automatically be updated any time footnote 15 has its number changed.

If you didn’t use the citation feature, though, I don’t think there’s a way to automatically update references like the one found in footnote 25.

well, but I did use it on a previous paper I was writing, without useing the citation feature. it was something about selecting all and a function key, but when I tried to do it again, it didn’t work - inserted codes for all of the footnote numbers.

Here’s what About.com says on working with footnotes and cross-references in Word:

However, it doesn’t. I inserted some new footnotes at the beginning of the paper, and the subsequent cross-references didn’t update automatically.