To ensure correct behavior of secured controls in this version, all calls to the Authorize function for controls placed inside other controls are now in the parent control’s PreRender event handler instead of the Load event handler. This ensures Authorize is always called after Ajax controls, such as the expand / collapse extender, and the Visible property of the control is properly set according to user roles.
After migration, re-apply any customizations you may have made to the Authorize() calls in your application.
Version 7.0 Application Migration