AutoCompleteExtender not working in Sharepoint 2010

This has been bothering me for a few days now. I'm trying to use the AutoCompleteExtender in a Visual Web Part project for Sharepoint 2010 but when I type in characters nothing happens. At first I thought it was an Ajax issue so I used the TextBoxWatermarkExtender and that works, so it must not be an ajax thing.

I followed this guys guide VERBATIM: http://ranaictiu-technicalblog.blogspot.com/2010/08/ajax-control-toolkit-with-sharepoint.html

Here's my ascx:

<%@ Register Assembly="AjaxControlToolkit, Version=3.0.30930.28736, Culture=neutral,         PublicKeyToken=28f01b0e84b6d53e"
Namespa开发者_高级运维ce="AjaxControlToolkit" TagPrefix="cc1" %>

<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>

<cc1:TextBoxWatermarkExtender ID="TextBoxWatermarkExtender1" runat="server"
 TargetControlID="TextBox1"
  WatermarkText="I'm awesome">
</cc1:TextBoxWatermarkExtender>

<cc1:AutoCompleteExtender ID="AutoCompleteExtender1" runat="server"
TargetControlID="TextBox1" ServiceMethod="GetCompletionList">
</cc1:AutoCompleteExtender>

Here's my codebehind:

using System;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;

namespace TestingAjax2.TestingAjax2
{

    public partial class TestingAjax2UserControl : UserControl
    {
        protected void Page_Load(object sender, EventArgs e)
        {
        }

        [System.Web.Services.WebMethod]
        [System.Web.Script.Services.ScriptMethod]
        public string[] GetCompletionList(string prefixText, int count)
        {
            string[] n = { "banana", "orange", "apple", "tunafish" };
            return n;
        }

    }
}

Any help would be appreciated. I'm working with one other guy and we're both completely baffled as to why it isn't working.

You cannot host Scriptservice methods directly in user controls, just pages.