I have an Adbrite account and recently, my code stopped showing ads. Instead it just showed the "advertise here" button. When I go on my Adbrite advertising page it says... This site is inactive. If this is your site, click here to retrieve your AdBrite HTML. Please copy your AdBrite HTML in its entirety, and paste it into your site, overwriting your existing AdBrite code. What does this mean?
Sometimes. With AdBrite. There are just no ads to display. Also. When you are new to AdBrite. You will often see that for up to 2 days or more. Sometimes people have said longer because there are just not enough advertisers.
I've had that happen as well - my guess is that your site has content that Adbrite doesn't approve of.