Part of the Folders appear with 0Kb and can´t be read

Hello everybody.

I´m struggling with a problem:
In a WD My Passport ultra, most of the folders can´t be read. They appear like a file with 0Kb that can´t be read. The info should be there because it seems the total space in the HD is taken).
I have use a couple of antivirus and anti-malware with no result. I have use a recovering program and it gets some files.

Any idea how to get my folders back?

thank you!!!