Mine broke yesterday too. Any idea how to fix the corrupted files?
It may be that Nikon Transfer 2 as included in ViewNX2 is the problem. ViewNX2 is NOT supported and the Nikon Transfer 2 included with it is NOT supported. Moreover it you check for an updated Nikon Transfer 2 from the one installed by the last ViewNX2 an UPDATED VERSION WILL NOT BE FOUND. It is probably time to install Nikon ViewNXi and use it rather than ViewNX2. If one is going to continue using Nikon Transfer 2 (which should be named Nikon Transfer 3, that is the one included with ViewNXi) install ViewNXi to get the latest Nikon Transfer 2.
Note that ViewNX2 writes to the NEF file when you do things like add stars. Since it is not supported at anytime it might start corrupting NEF(s).
Still using CaptureNX2 for NEF files? I recommend saving an NEF file for this specific use, e.g. copy D800_DSC9999.NEF to something like D800_DSC9999_CNX2.NEF. Now edit the copy. The original NEF will not be written to by ViewNXi and its Nikon Transfer 2 only a sidecar file such as D800_DSC9999.nksc. The same goes for CaptureNX-D. It will not write to the original NEF only to the associated *.nksc side car.
I have not fully tested this but I'm not finding that adding 5 stars to an NEF file in ViewNXi does not write to the NEF. This is all on Windows 7. I will install ViewNXi again on my iMAC and test it but my iMAC is running OS X v10.11.6 (El Capitan) and not OS X v10.12.x (Sierra).
Play it safe: upload NEF(s) with Finder FIRST and then try and see if ViewNXi and it's associated Nikon Transfer 2 cures the problem.
I hope this thread helps save someone's bacon!
Dave Hartman
I hope I found all the typos. I wrote this pretty fast. I'm reading on other forms about people having corrupted NEF(s). I'm trying to help so people don't loose valuable NEF(s)!