The developers of ProSeries are rather incompetent with creating those pop-up windows, so they can be rather problematic.

If you just need to close the window, try changing the resolution to your computer/monitor so you can see the "x" to close it out. 

Another possible option is to do Alt-Tab on your keyboard until the advertisement is highlighted, then try to close the window (maybe Alt-F4?).

Someone else posted a response for a good way that worked for them, but unfortunately, I can't find that post right now.