It seems to me that last year I ad co-op ads working. Then there were some problems in December, and I gave up on them. I just went through and reinstalled everything and it still does not seem to validate. It loads data into ad_network_ads_379.txt - so something is working.
How's your site setup? Is it a script that generates static HTML by chance? Because the main page shows that your ad_network file needs to be updated, yet that ad doesn't exist in your cache file, so either that's a statically generated page or you have more than one ad_network .txt file that it's referencing.
The index page was created by FrontPage, then renamed to index.php and patched to add the code ... ini_set... etc. It still had that code from last December but commented out. Yech - as I look at it to explain it - I see that although I changed it today to point to ad_network_379.php - somehow I did not save the changes and/or uploaded the wrong file, and that's the problem for the main page. Most of the rest of the site pages generates dynamic PHP pages, and that was changed correctly - as far as I can see, but it's not generating an ad. I put some echos in for tracing ad_network_379.php - it creates a line at the bottom of the page - and it seems to be processing ok. I have include ($sitebase . 'ad_network_379.php'); // this runs ok echo $ad_network; // but $ad_network has no value but If I put the line echo $ad_network; at the end of ad_network_379.php - it generate an ad on the page [same one all the time], however, my index.php then generates two ads.
Well something doesn't seem right... for one, the ads on any page (except the root) are all the same ad. It's not serving the impression tracking image, which makes me think they are static pages (same ad and no image). Try adding the echo to the ad_network file and removing the echo from the index.php page (the one after the include line).
I emptied the ad_networks_ads_379.txt file and that seems to be getting ad rotation working again. For some reason the echo $ad_network; will not work in the PHP file that creates the dynamic pages, the value is always blank at that point, it has to be as the last line in ad_network_379.php That maybe solves most of the problems, there are a few static non-PHP pages in the site that I will have to fix since they don;t display ads. I'll try again tomorrrow.