An Error Occurs When the WPF Themes are Referred Locally

Environment

Product Version	12.1.18.620+
Product	Progress® Telerik® Reporting

Error Message

An error occurred while finding the resource dictionary "/Themes/Office2016/Telerik.ReportViewer.Wpf.xaml". WinCont App.xaml

Cause\Possible Cause(s)

The XAML designer locks the theme files and they cannot be accessed by the application.

Solution

To prevent the undesired outcome, navigate to Tools -> Options ->XAML Desginer -> uncheck Enable XAML Designer. Restart the Visual Studio afterward.