Zero out your hard drive on Windows!
And YES, you can do this for Free!
What does writing zero to hard drive do?
Writing zeros to a hard drive is one method to sanitize a drive and ensure data is not recoverable. If you are selling a PC or hard drive, or even if you buy one form ebay to save a few bucks. This is a task you want to do first before you do anything. This method is also known as the Single Overwrite method, and called zero fill erase or zero-fill.
It is a process of replacing existing data on the hard drive with zeros, so as to prevent most hardware based and all software based recovery methods from extracting information from the drive. Therefore, when it comes to completely erasing sensitive files from hard drive, writing zero to hard drive is much more reliable than formatting a hard drive, which just makes data invisible to operating system by moving it to un-allocated space and can be easily restored by special recovery tools like FTK. This is the proverbial monkey wrench for forensic recovery!
Actually, Windows itself comes with a free zero fill hard drive utility, and it is used via the Command Prompt. It adopts a special format command to achieve the purpose of writing zeros to the hard disk.
Step 1. Click “Start” button, input “cmd” in the “Search” box, right click the pop-out Command Prompt icon and select “Run as administrator”.
Step 2. At the prompt window, type “format f: /fs:NTFS /p:1” command, and hit on “Enter” to format the f drive with the NTFS file system and write zeros to every sector of the drive for a single pass. For a twice pass, you can input “p:2” instead.
format f: /fs:NTFS /p:1
Step 3.Type “y” and press “Enter” to confirm erase data.
Warning: You cannot undo a format! So ensure that you choose the right hard drive and back up any required files! If you format primary drive by mistaken, the operating system will be deleted and your computer will not work again until you reinstall it.
Step 4. Wait for the process to be completed. After that, you'll be prompted to enter a Volume label. Type a name for the drive if necessary, or then press “Enter” to skip it.
Step 5. Wait while “Creating file system structures” appears on the screen
And there you have it, you have zeroed out the drive. If you are ultra paranoid you can due multiple passes beyond 1 or 2 as outlined above. DOD used to recommend an insane number, in reality one will do the trick for 99.9% of us.
— G. Love