I have a hierarchal radgrid control that consists of a master table and 2 detail tables which sit on a web form. The web form also has a text box on it that's used for querying the info you want shown in the grid. Initially the radgrid is not visible, so all the user sees is the text box when the app is launched. Upon data entry (same page is launched again through a response.redirect "Page name" in a button click event), the grid becomes visible and the data is loaded and bound to the grid through the NeedDataSource method. However when the page returns, the master table data is being shown correctly in the grid, but the row expander to get to the detail tables is not enabled which prevents the user from drilling down any further. I've got events to assign the detail datasource when the row is expanded, so I know it works. I've done test on the grid where I load the grid on the initial load based on some hard coded criteria and I'm able to drill down without having to set any other properties. Why is it that I can't do this based on user submitted data in a click event?