Telerik RadAjaxPanel returns 404

I'm trying to do a RadAjaxPanel ajaxRequest (invoked on the client) to call the server event-handler. I'm getting a 404. I do have a server-side AjaxRequest handler defined but it never gets call because of something with the request. 开发者_StackOverflow中文版What do I have to do to figure this out?

.NET 4.0, IIS 7.5, latest telerik.

Thanks.

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I would go with Firebug or Fiddler (for IE) to see how the request is initiated and when happens afterwards. Also check the web.config configuration - whether the behavior changes with Classic or integrated IIS 7 pool.