As we are all aware, deleting a file on a modern computer doesn’t really remove the file completely and permanently from your computer. It just merely marks the deleted file’s space on the drive as “vacancy” telling the system that this is free now for storing data in the future. Until these freed-up space gets overwritten by new files, your “deleted” file is in perfect shape being recovered by many data recovery tools out there.
It may not be a big deal if you are the only one using the computer. But it could matter a lot if the computer is shared by a group of people. What’s even worse is that when it’s time for a new computer you just throws out the old computer without wiping out data on the hard drive. Your privacy is in great danger in these two cases.
So, what should we do to make sure the files being deleted are permanently gone unrecoverable? And what’s the best practice to completely wipe out the old hard drive to make sure nothing left on it before being disposed of? Let’s check out.
Let’s check out.
Wiping out files on Windows
As we mentioned above, Windows built-in file deletion doesn’t really permanently delete things. What you need is a good 3rd party tool that acts like an instant file shredder. Eraser is one of the best I highly recommend. It’s free, open-source, fast, and convenient. Most importantly, it works. Once it’s installed, you can just right-click a file or folder you want to really wipe out of your hard drive, go to Eraser, and choose Eraser from the context menu. If the file is locked or opened at the moment, you can choose to Erase on Restart instead.
It also offers many interesting options, such as 13 overwritten methods, ranging from a slow 7-pass to a quick “First/last 16KB Erasure”, which guarantees that nothing will be left to be recovered by other recovery tools. What’s interesting is that it can even overwrite files or free spaces with a list of legitimate files found on your systems.
Of course, there are many others that can also do the job pretty well, including the famous Piriform’s CCleaner, and a few others we’ve covered before, Hardwipe, File Secure Free, and Jihosoft Eraser Free.
Wiping out the whole hard drive
Before you throw out your old computer, one thing you have to do is to wipe out the hard drive to make sure nothing on it that can be recovered later on.
DBAN (Darik’s Boot and Nuke) is one of the best out there designed for consumer use to prevent identity theft before recycling an old computer. It’s a Free Linux-based self-contained boot disk that automatically deletes the contents of any hard disk that it can detect. It prevents all known techniques of hard disk forensic analysis, a bullet-proof tool for PC.
If you have some old hard drives that need to be recycled, you can use some of the data wiping tools that run right inside your Windows system. Hardwipe and Active@ KillDisk are two of them that work quite effectively. While Hardwipe is a completely free tool that offers 6 wiping methods for each wiping operations, from 0 overwrite to Gutmann with 35 passes, Active@ Eraser only has a lite free version that only supports 1-pass overwritten method. But the latter has a feature to support SCSI hard drives.
Also, check out How To Use DiskPart to Securely Wipe Out An Entire Disk.
Wiping out the Servers
When it comes to wiping data in a server environment, I found Active@ KillDisk works quite good. Not only does it support a wide range of type of hard drives, including those SCSI-based RAID drives, but also offers a variety of wiping methods that help you meet different compliance requirements depending on where you are. You can use it right on your Windows system, as well as in a self-contained boot drive. Either one works exactly the same way, with a comprehensive user interface that is straightforward and easy to use and operate.
Wiping out SSD drives
Due to the unique writing mechanism designed in SSDs, none of the tools listed above will work well when it comes to SSD drives. Some researchers even revealed that the data from the SSD that has been erased is able to be recovered more than half of the times.
The best way to make sure an SSD you gave away or recycle don’t contain any of your personal data is to encrypt it. With proper software and long enough password, it’s guaranteed that nobody could ever recover your data from an encrypted disk. We have to mention TrueCrypt since we are talking about the encryption here. It’s a free, open-source encryption tool that can pretty much do everything, encrypt files to partitions, and to the entire drive, and operating system.
You can follow our step by step instruction to encrypt the whole system.
/Update on March 19, 2019/
Now since TrueCrypt has retired from development, you may try one of the alternatives instead. VeraCrypt is open-source and code audited, improves on TrueCrypt, works on Mac and PC, and allows the creation of encrypted containers.
Now you are aware of the truth of deleting files and hard drives in Windows, and know what to take and use to properly clean up your old computer and hard drive before handing them over to the others, there is no reason left why you should let your own data slipped away anymore. Besides, all most of the tools we mentioned here don’t cost you a penny to run.