I too am having a similar error to the OP
File format error found at
SAXParseException: '[word/document.xml line 2]: Attribute w:hAnsiTheme redefined
', Stream 'word/document.xml', Line 2, Column 43301(row,col)
I have tried methods 1 and 3 of the link, https://forum.openoffice.org/en/forum/v ... 88#p404588 don't have a clue how to do method 2 still can't open the file. The file has tried to be opened in MS Office to see if it can recover it and in desperation I changed the file extension to .odt and open it to see if that would help but no. Does anyone have any other methods I could try please? I have extracted the document.xml file and attached.
Edit:Helps if referring to a link to put it in there!!