I am not actually sure what do you mean by that show an empty message in RadHtmlChart. If this is an message that is shown when the RadHtmlChart has not data, then you can find useful this
forum thread. If, however, that is not your main point, could you please provide more information on this regard?
Note also that you can align any div/span elements with the desired content over the chart itself.
All the best,
the Telerik team
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