<td><asp:TextBox ID="tbTaskNumber" runat="server" ViewStateMode="Disabled"/>
                <asp:RequiredFieldValidator runat="server" ControlToValidate="tbTaskNumber" Text="*" ValidationGroup="vgTaskDetails" />
            </td>

<div class="epsModalFix" id="divModalMPD" runat="server">

protected void lbNewTask_Click(object sender, EventArgs e)
        {
             
            isMP = false;
            hfTaskID.Value = null;
            lbRevise.Visible = false;
            divModalMPD.Style["display"] = "block";
            divModalMPD.DataBind();
        }