Thank you for clarifying about the commented configuration. I indeed, missed that out.
Also, as we continued the discussion in the support ticket, you lastly mentioned the usage of the AjaxToolkit's script manager, which is an unsupported scenario. The resolution is to set the ScriptManager's CombineScript property to false as described in this forum thread
. Although, it is always recommended using the Telerik UI for ASP.NET AJAX controls with the native asp:ScripManager or the Telerik's RadScriptManager.
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