title: DomEvent. AddHandler
body: <p>I am facing little issue in my web application in asp.net.
  i am receiving the below error :</p>
  
  <p><em><strong>Error: Sys.InvalidOperationException: Handler was not added through the Sys.UI.DomEvent.addHandler method.</em></strong></p>
  
  <p>I have used  Updatepanel and this error occurs when i try to do some 2-3 actions very quickly.
  and when next time i try to do take some action my web application just hungs up.
  Please suggest.
  Thanks</p>