It is recommended to avoid nesting of RadAjaxPanel controls. In the scenario you describe the ajax request is handled by the outer RadAjaxPanel because the request from the inner RadAjaxPanel is canceled. Try closing the edit form and see what would happen. Also composite controls such as RadGrid need to be updated as a whole. If you would like to achieve partial ajaxification it is illustrated in this
online demo. Please take a look at this
article. The guidelines in it are generally the same when it comes to nesting RadAjaxPanel controls.
When handling more complex scenarios it is recommended you use RadAjaxManager control. It provides functionality for handling all scenarios where the RadAjaxPanel control has some limitations. You would find this
article useful regarding RadAjaxManager and WebUserControls.
I hope this is helpful to you.
All the best,
the Telerik team
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