Whether it's among friends, on E-Bay, in second-hand shops, or on platforms like pcbilliger.de: Used electronic old devices such as PCs, tablets, and smartphones can be bought cheaply and sold for good prices everywhere. Online sales platforms, in particular, are enjoying increasing popularity. If you also want to sell your used electronic devices, you should definitely keep one thing in mind: The complete removal of all stored data. Below, you will find some information on how to securely delete your data.
Formatting is not deleting
Unfortunately, it is still a widespread misconception that emptying the recycle bin or formatting a drive is sufficient to completely and permanently destroy one's data. With this type of "simple deletion," you are only recreating the hard drive's table of contents, known as the Master File Table (MFT). The previously occupied storage space of the deleted data is then marked by your operating system as content that can be overwritten. The data itself is still on the storage medium. You can restore it with simple tools and a few steps. This principle applies equally to computers, tablets, and smartphones.
Secure deletion means overwriting or encrypting data
Electronic devices, whose content you simply delete before selling, are therefore still full of sensitive information. This is because even data that you deleted many years ago - and whose existence you may have long forgotten - can still be on the device.
Therefore, before selling, use special software to completely and permanently destroy data. Depending on the tool, there are different methods.
Overwriting:
Especially with older hard drive models, the Guttmann method, named after its inventor Peter Guttmann, has proven to be extremely reliable. Here, the data on a hard drive is overwritten exactly 35 times with specific values and according to special patterns. This frequency of software-controlled data deletion is obsolete for more modern hard drives. Here, a complete but thorough overwrite is usually sufficient to securely destroy the data.
Encryption:
With this deletion method, you encrypt the data of the entire hard drive and then delete the containers. The corresponding password should also be destroyed, or not even written down in the first place. If the guidelines for creating secure passwords are observed, this encryption cannot be cracked. Nevertheless, the hard drive can still be used, as the encrypted data is simply overwritten with the new data.
Degaussing:
With this method, named after the unit of magnetic flux density Gauss, the data carrier cannot be used again afterwards. It is therefore only suitable for disposing of PCs, smartphones or tablets. This is because the data carrier is exposed to such a strong magnetic field that not only the information on the data storage, but also all information for hard drive control is lost. This method does not work with chip-based SSDs.
Conclusion:
Before selling, giving away, or disposing of your old devices, you should securely delete the data. Those who already own the SecuPerts Rescue Stick or the First Aid Kit from Engelmann Software already have this function on board with both mentioned tools. This allows you to overwrite hard drives in such a way that you permanently delete and destroy the data on them. With the SecuPerts Rescue Stick or the SecuPerts Rescue Stick, you can thus bring your PC into a state where you can sell or give it away without hesitation.
