Corrupted memory card. Advice needed.

Assuming you have not allowed any write operations on the memory card, you should be able to do a complete recovery.

However, to do so, you will need to use a real data recovery program, not one that that claims to recover just photos.  A real data recovery program will dig much deeper than a photo recovery program, and will not care what the data is.

I use Easeus Data Recovery for such jobs and have had excellent success on those occasions I have needed it.  Your files were not deleted, as such, so you would probably need to do a Partition Recovery.

Of course, it is also possible that whatever went wrong did write something to your memory card and so scramble some data.

I would perhaps suggest not to use the playmemories program to transfer your photos to the computer, but instead use a card reader and windows explorer to COPY the files to the destination of your choice.

Good luck.

--
The greatest of mankind's criminals are those who delude themselves into thinking they have done 'the right thing.'
- Rayna Butler