Basically, RadEditor is an HTML/XHTML editor and it cannot load, decode and
export to MS Word content. You should use a third party tool to convert the MS
Word document to HTML and after that you will be able to load the content by
setting the Html
property of RadEditor.
You can use the
provided code solution in the following help article:
Save In External File
to load any files in the editor, but note that its content should be valid
HTML/XHTML or plain text content.
the Telerik team