I have only had my website up for a few days, and I notice that everytime I go to the site, I get pop-up advertisements. I don't see them until I close my browser windows, and then there they are lurking in the background. We are a non-profit organization, and a couple of the pop-ups have not reflected our core values. Is there any way to make sure there are no pop-ups when people visit our site?

Thanks,
Liza