I found something: I made a new word document, it opened without a problem. Saved it, and close it. then I opened it, all ok.
then I went to file, open, to see the word document I want to open that gives me the error: I dont see it ,
It seems that office word can only see docx, odt, txt files and not doc files.
As the document I try to open and gives an error is an doc file.