I am afraid we are not aware of such kind of issue with RadChart. Our local tests show that the chart works as expected. Can you please provide more information about your setup -- ASP.NET version, IIS version and the relevant sections from your web.config file -- system.web and system.webServer. You can remove any information that you do not wish to show in a public forum or open a support ticket and attach it there. We will review it and get back to you with our findings.
the Telerik team
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