Multiple Read to .iso produces different file checksums

[FriscoBJ]

When I copy a DVD to disk multiple times and then compute the simple byte binary checksum of the file contents they never match each other.  Using FC /B in a Command Prompt window shows stretches of mismatch one of the files reports all zero bytes and the other file has data at the same offsets.

 

[LIGHTNING UK!]

Then you have a problem somewhere, they should be the same - assuming something isn't changing the data on the fly.

 

If your drive can't read something, it should be erroring out, not returning a bunch of zeros.

 

Turn on the option to make ImgBurn calculate and display the md5 of what it's read and double check the values between reads.