Secure Erasure

Contrary to popular belief none of the following actions removes a file from storage media. Instead, these actions simply remove the file from an index:

• delete
• move
• (re)-format

Software is available that can retrieve files that have simply been removed from an index. In order to prevent recovery of files from media being disposed of it is necessary to either:

• physically destroy the media (can be simplest for removable media such as floppies, CD/DVD, SD cards)
• run a "secure erase" program over HDD/SSD

Secure Erase

Risk of Inadvertent Erasure

In order to minimise the risk of inadvertently erasing wanted media:

• avoid installing erasure software to OS that are installed
• disconnect any HDD/SDD containing software and/or data that is to be retained
• boot a utility from USB/CD/DVD in order to run the erasure software

Well known utility systems that can be booted from external media and contain a thorough erasure app include:

• systemrescue CD
• parted magic