I have successfully implemented a Rad Splitter oriented horizontally, to afix a navigation bar to the top of the page, and a second pane, below the splitter bar, that displays the main content. In this pane, is a MSAJAX control toolkit TabContainer control, the tab with index 0 displays fine. But, when I click tab index 1 or 2, NOTHING DISPLAYS, just blank white space. I tried setting the RegisterWithScriptManager property to true of the RadSlitter control, but it DID NOT fix it. Does anyone know how to fix this?