anyone know a good program for comparing integrity of files and folders

Hi everyone; I copied some folders to an external drive and later sadly discovered many of the files in the folders were damaged, probably about 30%. Is there a program that I can use to compare folders quickly to identify which files are damaged. To do this one by one would be very slow and I am keen to keep as many files as possible. It would be good if the program could give the names of the damaged files for ease of identification. Thanks

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#1 My guess

My guess is that even though the files that were copied are dammaged, the originals are still ok. Maybe there is something wrong with the drive you coppied them to. try putting them on a different drive.

#2 If you don't mind getting

If you don't mind getting your hands dirty on the commandline, you might look into using rsync with the ---checksum flag.