Custom Validator is not work while submitting the form

 Iam going to submit the form and below  i am using a checklist box and using custom validator to validate it but its not going to work while submitting the form.
<form> <table style="color:#808080;font-size:13px;" width="100%" height="100%" > <tr> <td >Name <span style="color:red">*</span></td> <td style="padding-bottom:1em;" class="mar"><asp:TextBox CssClass="marleft90" ID="TextBox1" runat="server"></asp:TextBox> </td> </tr>
<tr style="padding-top:4em;margin-top:10px;"> <td >Contact no.<span style="color:red">*</span></td> <td style="padding-bottom:1em;"><asp:TextBox CssClass="marleft90" ID="TextBox2" runat="server" TextMod ...