title: "Invalid postback or callback argument" with Databound controls
body: <p>I am getting the following error when an event (Add/Edit/Delete) occurs on my databound control.</p>
  
  <blockquote>
    <p>Invalid postback or callback argument.
    Event validation is enabled using in
    configuration or &lt;%@ Page
    EnableEventValidation="true" %> in a
    page. For security purposes, this
    feature verifies that arguments to
    postback or callback events originate
    from the server control that
    originally rendered them. If the data
    is valid and expected, use the
    ClientScriptManager.RegisterForEventValidation
    method in order to register the
    postback or callback data for
    validation.</p>
  </blockquote>
  
  <p>I am using a custom DataList control, but this problem also occurs with GridView, DetailsView, FormView and Repeater control (and maybe with other databound controls).</p>
  
  <p>The answers I can find tell me to turn off the validation in the config file or page, but that does not sound like it is the best solution. What am I doing wrong?</p>