Some sites use regular HTML for ads while others use a plugin such as Flash. If you right-click the blank area, does it show an Adobe Flash menu or other plugin menu?

Perhaps you could give a URL or two where this problem occurs.

Hello, this are some url:

http://www.biglots.com/weekly-ad

http://localad.walmart.com/Walmart/Entry/Flash?storeref=1084&forceview=y

I can see them with Internet Explorer and Google Chrome, but not with Firefox. and I tried with right-click in blank area and nothing, in the page are all other information (text, links, etc.) is just not ad.

Thank you

Thank you for the links. On both sites, the default "broadband" view uses the Flash player, while the "Dial-up" or "HTML" view does not. Have you tried those other views?

Of course, Flash should work unless it is blocked or crashing for some reason. Have you noticed any problems with Flash media on other sites? Earlier versions of RealPlayer browser add-ons could cause Flash media to appear blank, so make sure all your Real Networks software is up-to-date. This article has a link for that: Flash 11.3 doesn't load video in Firefox.

If you notice any severe Flash issues, there are some other workarounds you can implement.

I upgrade real-player and that was the solution, thanks a lot.