Word document from .dotx Template

[FelixHerz]

Hey, I'd like to know how to create a word document, starting from a Word .dotx template.

The following code lead to an Error EOF in header

using (var fs = new FileStream("C:\\tmp\\" + _template1, FileMode.Open, FileAccess.Read))
{
    XWPFDocument doc = new XWPFDocument(fs);
    // ....
   
    var dataStream = new MemoryStream();
    doc.Write(dataStream);
    return dataStream;
}

Any help would be highly appreciated.

Cheers, Felix