When a file is deleted on a computer, it is not truly gone.The data remains on the drive until that area of the drive is written on. During this time, the deleted file can be restored with file recovery software. It is sometimes a dangerous thing, especially when the deleted file are confidential. So before you sell or donate your computer, make sure that you have deleted all files completely.
Step One: Download File Shredder and install it on your computer.
Step Two: Click “Shred Free Disk Space” link on the left column to remove the remnants of any deleted files. These remnants may exist in the free space of the hard drive, but you don’t remember having stored on the computer.
Step Three: Find the file you want to delete completely and drag it to File Shredder window.
Step Four: Click “Shred Files Now” button on the bottom of the window. When the shredding finished, click “OK.”