We are aware of this problem, however please note that Visual Studio 2013 RTM was made available on October 17, 2013. Therefore the current build of Telerik RadControls does not support this VS version. Hence there might be some inconsistent behavior or even unexpected errors showing up.
Currently, we are working on the known problems related to VS 2013, IE11 and .NET 4.5.1 we will include the fixes in our upcoming release. However, RadControls will support officially Visual Studio 2013 from Q3 2013 SP1 release.
you can check which the Visual Studio versions we officially support are.
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