If the document is on a USB drive that has been removed without going through the safe removal process, it is likely to be corrupted beyond repair - time to reload from a known good backup.

Otherwise, you might try using Word's 'recover text from any file' file opening option but do be aware that you'll only get back plain text (no images, tables, formatting, etc.) with that approach.

Cheers
Paul Edstein
[MS MVP - Word]

Make a copy and do some experiments to test if it true word document:
- right-click the file and under "properties" check if you can see "details" tab with a part of word document features: author, template, number of paragraphs etc.,
- test if the file was not converted to "pdf" file: change extension to pdf and try to open with pdf viewer,
- change extension to zip and open the archive, if you can do it, you can try to find programme that could open the file in one of zipped files,
- change extension to txt and see if you can see any hints about creator in the plain text file.

combo

Try to open it with OpenOffice or LibreOffice. I found that those can sometimes open files that Word cannot. If it opens, add a space anywhere and save.

"Knowledge is power. Information is liberating. Education is the premise of progress, in every society, in every family." (Kofi Annan)
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Hello.
Thank you for taking the time to share how to go about fixing this. I tried everything you guys suggested.I still getting this error:((

At least in case of first and two last points from my post you shouldn't get any errors, rather tell if you found any hints.

combo

Upload your file here https://onlinefile.repair/en/word.html and reopen it

Thanks for help