Photography

Hey everybody, so long story short, I had an uncle who recently passed away with cancer, before he got sick he spent a lot of time photographing in his free time (using nikon), as I have done a little photography (I use canon, sorry nikon), she asked if I could help with recovering some photos that they didn't manage to open before he passed.

It is .NEF files, when I try to import them in lightroom it says "this file does not contain a supported format (or it might be damaged)", I have tried to open them in diffrent image viewing tools and recovering softwares which should be able to open/use NEF files, but they all said that the format was wrong. It also says the size is 31MB.

She mentioned that it was files older than three years, but from what I have been able to find out, I don't think that age is the problem, I suspect the files have been corrupted at some point.

Any help or suggestions that could possible save the images would be greatly apreciated, but both my aunt and me are aware that it is a very big possibility that they cant be saved.

Thanks in advance :)

Also, new to the subreddit, if this post should be a comment to that gear post, please say, and I will post it there instead :)