Hello
This quote from the mentioned article does not seem to be correct, or for some reason it does not work for me, when using RadGrid within an UpdatePanel:
"Since Q1 2016 the default built-in export buttons are already performing regular postback, therefore it is not needed to manually exclude them from Ajax, even the RadGrid control is ajaxified, to perform export with them."
I am using UI for ASP.NET AJAX 2019.1.215.45. It only worked for me by adding CommandItemTemplate with custom buttons and setting "args.set_enableAjax(false)" for specific export to Excel button.
Cheers,
Roger