Thank you for contacting us.
The Telerik VS extensions that are part of Telerik Extensions for ASP.Net MVC Q2 2012 - Version 12.2.607.0 are not ASP.NET MVC 4 RC compatible. The latest VS extensions available in the Visual Studio Online Gallery are compatible so you just have to update them through the Visual Studio Extension Manager. Here are the steps to follow:
1.Run Visual Studio and launch the Extension Manager from the Tools menu;
2.Navigate to the Updates section;
3.Locate the 'Telerik MVC VSExtensions' package, update it and restart Visual Studio;
Note that it is strongly recommended to update all the Telerik VS extension to avoid possible version problems.
I hope that helps. Please write us again if you need any further assistance.
the Telerik team
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