I have a textbox (myTextBox) where the user enters a number. They then click a button (myButton) and that in turns enters it into a listbox (myListBox). How do I prevent duplicates from being entered into the listbox?
So if the user enters: A
then B then A. It should not allow A to be entered a second time.
How can I do this? In Access 2003?
Thank you in advance.