USB files are recovered but can not be opened

I used Recuva to recover deleted files (word and excel) from my USB stick. The files are recovered and I placed them on my hard disk (with enough space), but when I try to open it i got notification '‘cannot open file because the file format or extension is not valid, check that the file is not corrupted and that the extension matches the format of the file.’. In my opinion the files are not corrupted and the extensions are correct. What can be wrong? How to solve? N.B.: my USB stick was protected with a password is that an issue?. Thanks

Assuming that the recovered files are the size you would expect and not just 0KB, then that sounds as if there is something wrong with the file headers of the recovered files.

Try this: Open a document after a file corruption error - Microsoft Support

If that doesn’t work then you could try one of the free online file repairers such as: Repair Corrupted File Online Free with AI Solutions
There are others which a quick websearch will find.
I just picked that one at random, I haven’t tried it myself.

Thank you very much! I tried this but it doesn’t work. I’m not sure but I think that that is because I have secured the documents with a password. Do you have other tips? Thanks

It may well be something to do with the passworded stick, but I wouldn’t know.

Have you tried copying a couple of the recovered files back onto the stick and seeing if they will open from there?
(I’m thinking that there may be a decryption key ‘hidden’ on the stick).

Not too many of course because whatever you write to the stick now will probably be overwriting what had been deleted - and you may want to try another revovery on those later, maybe with a different recovery software to see if that gives the same problem.

Thanks again. I tried, als other recovery software, but did not work. By the way: the documents itself are also passworded. Maybe it has to do with that and mavy you have an idea. Thanks