There should be no problem to set German localization for your application. You need to set the CurrentCulture and CurrentUICulture:
Thread.CurrentThread.CurrentCulture = new CultureInfo("de");
Thread.CurrentThread.CurrentUICulture = new CultureInfo("de");
Furthermore, you need to have the folders containing the resources for the German localization in the structure of where your binaries are placed and referenced.
the Telerik team
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