Telerik AJAX Controls could be effectively tested using different UI Testing frameworks however each of them has specific advantages and limitations. You could find more information in the following article TestStudio-versus-VS2010-Comparison. In some cases not all of the tools have the ability to automate dynamic interfaces and complex AJAX applications entirely. That's why Telerik offers third-party solutions for more effective test automation:
1. The free Telerik Testing Framework which helps you automate AJAX, Silverlight and WPF applications using coded steps for free.
2. WebUI Test Studio which has the options to record, execute and debug functional tests with the Visual Studio environment.
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