in reply to MS Word conversion

recreate the original MS Word document from that text file

I think it is safe to say you can forget about that. Not a 100% anyway. Also there are quite a few versions around ranging from .doc (Word95) to .docx (Word 2007). You don't mention your specific format.

My goal is to automate some changes to a set of MS Word documents.

I think you better try your luck with some VBA macros (Uff).

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