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Any ideas?

Here is the code for the dropdown lists

<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">


<table border="0" cellpadding="2" cellspacing="0" width="500">
    <tr>
        <td width="100">
            <b>Select Category :</b></td>
        <td>
            <asp:DropDownList ID="ddlCSRs" runat="server">
            </asp:DropDownList>
            <ajaxc:CascadingDropDown
           
            ID="CascadingDropDown1"
            runat="server"
            Category="category"
            TargetControlID="ddlCSRs"
            PromptText="[Select CSR]"
            ServicePath="cascadingdataservice.asmx"
            ServiceMethod="GetDropDownCSRs">
            </ajaxc:CascadingDropDown>
           
        </td>
    </tr>
    <tr>
        <td>
            <b>Select Product :</b></td>
        <td>
            <asp:DropDownList ID="ddlAEs" runat="server" OnSelectedIndexChanged="btnSearch_Click" AutoPostBack ="true">
            </asp:DropDownList>
            <ajaxc:CascadingDropDown ID="CascadingDropDown2" runat="server"
            Category="product"
            TargetControlID="ddlAEs"
            ParentControlID="ddlCSRs"
            PromptText="[Select AE]"
            LoadingText="Loading AEs..."
            ServicePath="cascadingdataservice.asmx"
            ServiceMethod="GetDropDownAEs">
           </ajaxc:CascadingDropDown>
           
        </td>
    </tr>
   
</table>
</asp:Content>

Code Behind

protected void btnSearch_Click(object sender, EventArgs e)
    {

    }

Thanks

-D