title: What are the Advantages of Using OnAsyncPostBackError over Page_Error
body: <p>I am currently researching an exception handling architecture for our App. </p>
  
  <p>We will be using <code>UpdatePanels</code> extensively and we will also be calling Webservices.</p>
  
  <p>I want to know if there is any real need to implement a <code>ScriptManager.OnAsyncPostBackError</code> handler compared to, the <code>Page_Error</code> event which seems to catch all exceptions that are thrown in the app.</p>
  
  <p>The only benefits appears to be the possibility to customise error messages, but that can be achieved if you have access to the <code>Scriptmanager</code> object itself.</p>
  
  <p>Are there any situations where the <code>AsynchPostBackError</code> will catch something the <code>Page_Error</code> won't?</p>