Microsoft JScript runtime error: 'Sys.Extended.UI' is null or not an object

Question

I have a problem on my page. When it opens, it displays the following error message:

Microsoft JScript runtime error: 'Sys.Extended.UI' is null or not an object

<ajax:ToolkitScriptManager ID="tsm" runat="server" CombineScripts="false" >

    </ajax:ToolkitScriptManager>

and display error

$create(Sys.Extended.UI.ModalPopupBehavior, {"BackgroundCssClass":"modalBackground1","DropShadow":true,"PopupControlID":"ctl00_ContentPlaceHolder1_panelPopupAddDefaultAddress","PopupDragHandleControlID":"ctl00_ContentPlaceHolder1_panelPopupAddDefaultAddressDragHandle","dynamicServicePath":"/SJM.Framework.Website/Order/ActiveOrders.aspx","id":"ctl00_ContentPlaceHolder1_modalPopupAddDefaultAddress"}, null, null, $get("ctl00_ContentPlaceHolder1_hiddenTargetControlForModalPopup"));

Can anyone tell me me what is the problem is. I've tried, but I haven't found it.

Answer 1

I got this error because somewhere I was using ScriptManager instead of ToolkitScriptManager. The moment i replaced Script Manager with Took kit script Manager application started working fine.

Hope this helps someone!