I'm having trouble getting autocompleteextender (from ajaxcontroltoolkit) to fire when it is on a user control (it works fine when everything is on an aspx page. In my case I'm using a master page as well as a user control.

Here's what I have.

On the masterpage (path: masterpages/MasterPage.master)

        <asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server" EnablePageMethods="true">
    </asp:ToolkitScriptManager>

On the user control (path: controls/sitenavigation/usercontrol.ascx)

    <asp:TextBox id="txtSearchInput" Runat="server" CssClass="searchinput" Columns="95" MaxLength="95"></asp:TextBox>
<asp:AutoCompleteExtender ID="txtSearchInput_AutoCompleteExtender" 
    runat="server" DelimiterCharacters="" Enabled="True" 
    ServiceMethod="GetSuggestions" ServicePath="~/App_Code/WebService.asmx"
    TargetControlID="txtSearchInput" UseContextKey="False" MinimumPrefixLength="2">
</asp:AutoCompleteExtender>

On the Webservice (path: App_Code/WebService.cs)

    [System.Web.Script.Services.ScriptService]
public class WebService : System.Web.Services.WebService
{
....
[WebMethod]
public string[] GetSuggestions(string prefixText, int count, string contextKey)
{
    //my code to return string[]
}

It seems that my problem is with my ServicePath in the extender but I just can't seem to figure out what it should be, any help would be great.

Thanks.