I copied several video files (VOB type, 1.4 to 2 GB in size) from one USB hard drive to another. At the target destination several of the files had defects. They were in general not completely unreadable. Most would still play but had a few scrambled frames. They play on a Blu-ray player but on a PC will cause the VLC video player (1.1.10) to crash.
I have not yet noticed any other file types like Word or Excel files being affected though it may happen undetected is quite scary.
My question now is how does this happen and how can this be detected/prevented.
Doesn’t Windows 7 have some kind of an integrity check when copying files?
Also is there any good software to compare files for being exactly identical down to the last bit? Ideally with the capability to compare whole folder contents so that it hasn't to be done file by file.