title: Html Tag in textbox/input text
body: <p>When I input some html tag like <code>&lt; b&gt;</code> or <code>&lt; test&gt;</code> (without the space after "&lt;") in my TextBoxes, When I submit the form I got the issue:</p>
  
  <blockquote>
    <p>Sys.WebForms.PageRequestManagerServerErrorException: An unknown error occurred while processing the request on the server. </p>
  </blockquote>
  
  <p>The status code returned from the server was: 500</p>
  
  <p>I don't want to set the "ValidateRequest" false, because of security problems.</p>
  
  <p>I thought in make some kind of javascript function inserting a space after "&lt;", this could work...I guess.</p>
  
  <p>Any idea?</p>