Hi DonRH,
(assuming you are working with a form and placing code in that form, also assuming that you are not getting any properties and methods after typing the name of you listbox)
select the listbox and check the "name" property (rt-click: properties). this will rule out typing errors
if the code is in a module:
add the form name as a prefix to the control name
i.e.
form1.listbox1.additem
Tallman64
p.s.
also try adding
DIM listbox1 as listbox
to your code