I’m doing a backup on my Samsung rv420 running Windows 7 Home Starter Edition.
In order to do it, I want to ensure that when making a copy from my computer to a external device, the files being copied do not change in the slightest. For that, I’ll do the next: I’ll take a file from my computer, copy it in the external device, and then copy it again from the external device to the computer. So the file has “traveled” trought the device, and I want to know if it's changed or not.
I know little abut hash functions. I have a program called FileMenu Tools that includes a function for calculating a couple of different hash algorithms. I hope the program does it job properly.
I did what I described with a file, I, logically, ended with two files, original and a copy I left in the desktop. I calculated the hash function and it wasn’t the same.
I don't know why is this. The hash varies upon in which directory is located a file?
What can you recommend me to achieve what I want, which is checking a file is exactly the same after traveling trought external device?