|Wallpaper ads which consist of two SWF files or two redirects it may happen that the preview of one of the two or both advertising means no banner displays. The background for this is usually in the programming of the Flash file:|
In a wallpaper a movie/animation should run synchronously on both ad parts. For this purpose the two Flash files must mutually deny to start simultaneously. If the preview is called only one ad part, this attempt with the (in the preview does not exist) to vote second advertising midsection and gets no answer. Depending on the programming of the ad and how to deal with this situation, it may be that the creatives then displays nothing (Flash object is embedded in the side, but remains transparent / invisible).
The missing display of one or both creatives thus does not necessarily mean that the ad is not working: Since in live operation both wallpaper parts are displayed in the same browser window, they may find each other and can synchronize and start the animation.