I made a timer that generates the alphabet and numbers,
then adds them to a listbox. Every so often it generates
the same thing, by the time is does do that the list has
around 200-1,000 items. If I put the Kill Duplicates function in the timer, it slows the timer down by checking the listboxes for duplicates. There must be an API function that maybe searches/kills the duplicates quicker and more effiently.

I think what I'm doing is manually adding.