Asp.net validation is not working for website forms

Question

Please visit http://www.wavetec.com/DownloadBrochure.aspx and see if we submit the form without filling the fields, it give an error. same with all the contact forms mentioned on left side bar.

This validation was working perfect but suddenly it stops. We have this working fine at http://es.wavetec.com/DownloadBrochure.aspx this is our Spanish version.

Any suggestions or ideas would be appreciable.

Code

<asp:TextBox ID="txtFullName" runat="server" CssClass="textfield" style="height:15px;"></asp:TextBox> <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="txtFullName" Display="Dynamic" ErrorMessage="Name Required" ValidationGroup="Brochure">&#8249;&#8249;</asp:RequiredFieldValidator>

Answer 1

Problem in your validation control

Error: TypeError: ctl00_UCNewsLetter1_RequiredFieldValidator1 is null 
Source File: wavetec.com/DownloadBrochure.aspx 
Line: 855