Hi I am getting the exception: "Error Loading Radchart" on my application whenever the "authentication" tag is set in my web.config. If I run the application without using the "authentication" tag then it works.
I am afraid that we are unable to reproduce the problem on our side.
You can find an attached sample web site to this thread (Telerik.Web.UI.dll has been removed), illustrating simple form authentication. RadChart is loading properly and as well authentication tag is recognized.
We would suggest you to send us a runnable sample application demonstrating the erroneous behavior so we can investigate it locally and provide you with more information.