I am trying to back up a large (160gb) folder on one external hard drive to another external hard drive, and want it to be compressed. I used the "Full" backup setting, but it didn't compress. Any ideas? Do I need to select "Mirror" and then set "compression"?
Are the files in destination included into a zip archive? If yes, that means they are compressed.
Please note audio files (as mp3 files) are already compressed and you cannot compress them more than that.