CCleaner for Mac has two methods of secure deletion: a Simple Overwrite (1 pass) and Medium Overwrite (3 passes). A 'pass' refers to how many times CCleaner writes over the spot on the hard drive. The more times CCleaner writes to that spot, the harder the file will be to recover by any means. The drawback is that it will take CCleaner longer to complete the job.
To set the method for secure deletion:
- In the left pane of CCleaner for Mac, click Options, and then click Settings.
- Select the method for deletion. If you select Secure file deletion (slower), you can specify how many overwrites CCleaner will use in the drop-down box.
Note: CCleaner can only delete files (including secure deletion) which have not yet been deleted from the Trash.