I am sorry to hear that you are experiencing issues after upgrading to the latest version.
In order to help you resolve the issues on your side I will need some more details. Can you share what are the exact problems that you have encountered? Any screenshots or error messages representing the problem would be helpful. Is it possible that your projects need to be updated using the Telerik Upgrade Wizard available in Visual Studio?
I look forward to your answer so that I can help you quicker.
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