Could you please explain in more detail what is the RadXmlHttpPanel used for? By design the RadXmlHttpPanel should be used for loading static HTML from the server, or a WebService, and the calls to the server are initiated from the client using the RadXmlHttpPanel.set_value("value")
Moreover the controls within the RadXmlHttpPanel must not initiate postbacks, because the state of the controls will be lost.
A sample source code that shows the issue will help us a lot in resolving it.
the Telerik team
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