I have ad tags (i.e. JavaScript) from several popular ad networks (AdSense, AdBrite, etc.) and I like to test them (basically make sure they render correctly) before adding them to my websites. I add the tag to a page, and end up loading the page several times on my dev box.
I noticed that after several refreshes on my dev box, the ads stop rendering. If I wait an hour or so, the ads start appearing again. I have a guess about this behavior, please let me know if this is correct:
- Ad networks like AdBrite sometimes serve CPM ad inventory. The advertiser is billed for the number of impressions
- So, to prevent bad impressions (like me refreshing on my dev box :D), they cap the number of impressions I get, probably based on my IP and referring URL
A follow-up question: how do devs who deal with ad tags test their rendering? It gets really annoying if the ads stop rendering after a few refreshes.
I think you have answered your question yourself here. You know why 🙂
In my experience most of the ads render properly so never had an experience where I had to check it properly. But why do you need to refresh it multiple times? Try to do as many changes as you want and then refresh.
Another option is to use tools like firebug where you can edit the html rendered and play with it. Once you get a proper design you can change your original file.