memo box in access 2000 or vb that comes with it

[Nath]

i've got a memo box in a form in access 2000 and on a click button i need to be able (or the user) to modify the text in the memo box, that's no probleme. the problem is when they (user) see that they didn't wnt to modify the memobox and want the old text to stay (no changes done).
can someone help me please.
thank you