raw - Corrupt NEF files

I had some NEF files in a folder that I didn't do anything with.
When importing them in Lightroom, no previews and a "file unsupported or damaged message"
So I tried with Nikons ViewNX, nothing. Even not in DxO or PhotoMechanic.

I had a look with EXIFTool and the corrupt file prints me only this:

ExifTool Version Number         : 8.39

File Name                       : _DSC5559.NEF
Directory                       : /Users/tunafish/Desktop
File Size                       : 12 MB
File Modification Date/Time     : 2010:11:29 12:46:56+01:00
File Permissions                : rwxrwxrwx
Error                           : File format error

I saw another question on photo.stack Damaged RAW (NEF)-files: ideas? and tried to copy over the makernotes from a good file (_DSC5556.NEF) with

exiftool -tagsfromfile _DSC5556.NEF -makernotes _DSC5559.NEF

but EXIFTool gives me this error

Error: Not a valid TIFF - _DSC5559.NEF
0 image files updated
1 files weren't updated due to errors

I have uploaded 2 NEF's, with _DSC5559.NEF being the corrupt one here:
Corrupt NEF files