i have an unbound text box in a form, and i would like that when a user selects a value from this combo box he clicks a button and that value would become the default value for a particular field in a table.
You could also try this by getting hold of the table definition in code and then changing the default values for various fields. This is a bit harder to do, though, and won't work if data in the table is already being looked at by a form, by another access object, or by another user.