My main page is a static page and adsense ads won't show up on the main page. I tried putting them in the text of the page and in widgets. The ads show up on all other pages and even if I preview the main page. However, if I browse the page normally no ads show up. I tried disabling all the plugins and I never put in custom CSS. One site is privacy.net but I am having the problem on several sites.

1) Never use a caching plugin while developing or making changes to a site.
2) what happens if you make the blog page the front page?

I tried disabling all the plugins and I tried toggling between a static page and the blog as the main page. I still have the problem. If I use: http://privacy.net/?preview=true it works, http://privacy.net/ it does not. Every other page it works, just the main page is the problem.

edit: I also tried resetting all the theme options and I am getting the same behavior.

edit again: I tried the Wordpress Classic them and the same thing happens there so it looks like it is not related to the theme. I am really confused now.

If it happens with another theme then you might try contacting the plugin author

It looks like it is an adsense issue. Usually it happens if people have more than 3 ad slots on 1 page but that is not the case here so I contacted adsense to see what the issue is.