Since Q2 2014 the installation of the Telerik UI for ASP.NET AJAX suite provides you with the Telerik.Windows.Document assemblies. With their capabilities you can extend the Export/Import to Word/RTF functionality of the RadEditor control.
Information about the provided libraries, their purpose and how to get them is provided in the Included Assemblies article.
You can follow the Import and Export to DOCX by using the Telerik Document Processing library code library for guidelines about the integration.
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