You need to select the project of interest in the Solution Explorer first. Another way to do it is through the context menu of the project (right-click the project that you want to convert and search for Kendo UI menu entry).
I want to mention two points to keep in mind:
You need to have the Kendo UI for MVC VSExtensions installed. You can easily get them through the Visual Studio Extension Manager | Online Gallery tab.
The conversion options is only available for MVC3/4 projects.
I hope this helps.
the Telerik team
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