When you delete files, folders, or even entire disk partitions using Windows Vista tools, the methods you use make it possible for items to be recovered using a variety of tools. For cases where the data you delete must be erased and unrecoverable, you need to turn to third-party tools like Eraser and Darik's Boot and Nuke. Keep the following points in mind when it comes to deleting files, folders, settings, and drives:
Erase sensitive files using a program like Eraser to ensure they cannot be recovered.
Use the highest number of passes possible when choosing a secure file deletion method. At 35 passes, the Gutmann method offers excellent protection.
Periodically erase your Internet and file activity trails using a program like CCleaner to improve personal privacy.
Prior to donating or giving away an old PC, take the time to securely erase its hard drive using a tool like Darik's Boot and Nuke.