Follow the steps below to get rid of system junk and iTunes junk with a Mac junk cleaner.Ī dilemma in cleaning up Mac is that after you have deleted all the unneeded files you can find - documents, videos, photos, audio files, applications - your Mac is still having low disk space. Cleaning up junk files is an effective way to regain free space on Mac. Summary: When it is cluttered up with junk files, your Mac will report low disk space.