The When Shredding Files, Use this Many Passes setting specifies the number of passes (or writing procedures) Identity Finder will take to overwrite the space used by a shredded file. Shredding a file is more secure than recycling or deleting because it uses this overwrite procedure. The higher the number, the longer it will take to perform a shred.
To view or modify this setting, click the Configuration ribbon, then the Settings button. For additional settings please refer to Change the Behavior of the Actions Used to Protect Identities or Settings to Customize Your Experience.