Object reference not set to an instance of an object. at ctrCityFlag.SetControl(Page page) in c:\Websites\contentmanager\controls\rendering\course-overviews\ctrCityFlag.ascx.cs:line 28 at ctrCityPage.SetControl(Page page) in c:\Websites\contentmanager\controls\rendering\course-overviews\ctrCityPage.ascx.cs:line 38 at RenderPage.Page_Load(Object sender, EventArgs e) in c:\Websites\contentmanager\RenderPage.aspx.cs:line 30