i want to implement ajax hover menu and i have a grid gridview1 like this

<asp:GridView ID="GridView1" OnRowCommand="ScheduleGridView_RowCommand" runat="server"
                                                AutoGenerateColumns="False" Height="60px" Style="text-align: center" Width="869px"
                                                EnableViewState="False">
                                                <Columns>
                                                    <asp:BoundField HeaderText="Topic" DataField="Topic" />
                                                    <asp:BoundField DataField="Moderator" HeaderText="Moderator" />
                                                    <asp:BoundField DataField="Expert" HeaderText="Expert" />
                                                    <asp:BoundField DataField="StartTime" HeaderText="Start">
                                                        <HeaderStyle Width="175px" />
                                                    </asp:BoundField>
                                                    <asp:BoundField DataField="EndTime" HeaderText="End">
                                                        <HeaderStyle Width="175px" />
                                                    </asp:BoundField>
                                                    <asp:TemplateField HeaderText="Join" ShowHeader="False">
                                                        <ItemTemplate>
                                                            <asp:Button ID="JoinBT" runat="server" 
                                                                CommandName="Join" Text="Join" Width="52px" />
                                                        </ItemTemplate>
                                                        <HeaderStyle Height="15px" />
                                                    </asp:TemplateField>
                                                </Columns>
                                            </asp:GridView>

so i registered <%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>

and added

I added this way in code of gridview columns

But i am getting fixed Edit/delete link in a new column rather than Hover menu,,Can any one tell me the solution to get hover menu