I have a digital signature generated by a smart card for a word document, i need to embed/add this signature to the word document programatically using either c# or c++.
I don't know how that digital signature compares to those created from a certificate, but you could look at the cmdlet in the PowerTools for OpenXML that adds a digital signature to Word document. You may also need to examine a Word document with the signature on it using the Open XML Package Editor Power Tool for Visual Studio.