The prog might have installed itself in your 'start' folder and put a shortcut in there - sometimes they do.
Navigate to it and delete it - there are various ways to get there. It might even show itself in your system tray: if so, right click and look for a delete/uninstall option.
It might not be easy to get rid of: that's how the blighters persist and keep throwing ads in your face!
There may also be an entry in your registry...
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Me, sweat? I'm that cool, it's condensation.