I'm new to AJAX. I'm trying to use the HoverMenuExtender control in a VS 2005 project. I'm getting the following error:

Error 5 The type or namespace name 'HoverMenuExtender' could not be found (are you missing a using directive or an assembly reference?) C:\Inetpub\wwwroot\OGIDW\CheckDetail.aspx.cs 174 13 http://localhost/OGIDW/

I have a reference to AjaxControlToolkit.dll in my project. So, I don't think it's an assembly reference. Am I missing a "using..." statement?

My statements are:

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

The code I'm using is

protected void grdPortfolioSummary_RowCreated(object sender, GridViewRowEventArgs e)
if (e.Row.RowType == DataControlRowType.DataRow)
HoverMenuExtender hoveMenu = (HoverMenuExtender)e.Row.FindControl("hoverMenu");
e.Row.ID = e.Row.RowIndex.ToString();
hoveMenu.TargetControlID = e.Row.ID;


Any help is much appreciated. Thanks in advance.