File format error found at
SAXParseException: '[word/document.xml line 2]: Attribute w:hAnsiTheme redefined
', Stream ‘word/document.xml’, Line 2, Column 46268(row,col).
If you are good with xml editing, try the following: make a copy of the file, change the extension of the copy to .zip, open the archive, extract the file document.xml, open it with a text editor that can save in Unix style format (with just a CR at the end of a line). Find the offending location and remove the second occurrence of w:hAnsiTheme. Save, put back in the copy, change extension to docx, try to open. If more similar errors are found, repeat the procedure.
If you are not good at this, register at http://forum.openoffice.org/en/forum/ , (provide a fake OpenOffice version for your signature and change that once your account has been validated), then ask for help there. You will have to upload your file there or at a file exchange service.