Keensie,
To turn the others off, you need an AfterUpdate event procedure for each
checkbox. Code for the first one would be the following; others are simliar.
If Me![FirstCheckBox]=True Then
Me![SecondCheckBox] = False
Me![ThirdCheckBox] = False
End If
However, unless you have some unusual reason for using three separate
fields, this is an ideal application for an Option Group, which stores a
different value in a single field depending on the selection. Only one
option may be selected at any time, so no code is required to deselect the
others. An option group can use either radio buttons, checkboxes, or toggle
buttons.
Sprinks