OK, I get your point about the backups being different than files on the given drive, The comments were not so much directed to you, but to help anyone reading these comments, as there are folks who DO think that duplicate files on the same drive are “back-ups”.
The piracy comment was also not directed expressly to you, but to anyone reading the comments. (I purposely did not accuse you of piracy.) During the year-plus I have been reading these forums, there have been quite a few people who complain about some video they downloaded via Bit Torrent, etc. not playing on WDTV, and to anyone like that, my comments stand. I request they do not waste our time asking the Community to help them with a file of questionable origin, integrity, quality, efficacy, etc.
Now, back on topic: So, did this file that showed on WDTV as 0 bytes appear that way when you reconnected the drive to your PC and you took a look? If so, and you knew it was not that way before; agree, something nefarious appeared to happen to that file; perhaps as you assert, caused by WDTV. As a WDTV user, too, I hope that wasn’t the case and hope there is another explanation.
We have occasionally downloaded a music track from our eMusic service that contained all the track info and even loaded into iTunes, but was actually 0 bytes. (Of course, it could not play, and the track from eMusic was the defective one, and it carried the defect over into iTunes.) Re-downloading the file was the solution.