Thank you for contacting us.
The exception that you describe does not seem to be caused by the Telerik controls (for a simple test I would suggest that you use any other control and check how the application will behave). Please take a look at the following article that I believe would be very helpful in resolving the issue that you get - System.Web.AspNetHostingPermission Error
I hope this helps. Let me know if you have any other questions that I can assist you with.
the Telerik team
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