I think this issue is resolved, though...What I didn't understand is that when the form is first executed, the list index is -1, no matter what value is displayed to the user.


When form is first executed there is no value displayed to the user. The user sees everything in the listbox that is within the height of the listbox and no item is selected by default.

You cannot do this

intSpcSize = CInt(List1.Text)

if you have not selected which item in the listbox you want. List1.Text is null if you do not select an item and you will get the type mismatch.

All you have to do is to accept this as is.