I would suggest you to carefully review and apply the needed configurations to your project, described in the Deployment section
of our Documentation.
If you still experience the same problem after following those instructions, I would ask you to give us some more details on the scenario in which you experience the the above problem.
Do you need help with upgrading your ASP.NET AJAX, WPF or WinForms projects? Check the Telerik API Analyzer
and share your thoughts.