Information that disappears from the trash can still be stored on computers’ hard drives
Experts advise to verify the removal of personal data and information before selling or disposing of computers, especially if this data includes information on other parties such as relatives, acquaintances or business partners.
The German Federal Office for Data Technology Security stated that the information that disappears from the trash can remains preserved on the hard drives of the computers, since the process of emptying the contents of the trash only refers to removing the data from the contents record.
Is the hard drive encrypted?
Patrick Bellmer – from the German “Heise Online” communications portal – advises the need to check whether the hard drive is encrypted or not, and in the event that it is encrypted similar to modern Apple Mac devices, all that is necessary is to remove the user’s account only, and this is done as happens when resetting the phone Smart, although the personal data remains, no one can access it because it is encrypted.
The encryption process is carried out in Apple devices through the security chip “T2” (T2), and is usually integrated into all new models, and the user can block the operation of devices in the event of theft, for example.
Bellmer explained that there are free tools that write on the hard disk in an “encrypted language,” such as “Disk Wipe”, “HD-Shredder” or the built-in “DiskPart” tool. On computers equipped with Microsoft Windows, it is a hard disk partitioning program.
The DiskWipe tool completely removes data from the hard drive, so that it cannot be recovered again even by professionals.
This tool can also be used to remove data from USB flash drives or SD cards and mobile devices.
However, these tools cannot remove the hard disk partitions on which the operating system is installed, and if the user wishes to sell or dispose of his computer, it is also best to remove the data from the operating system partition.
In this case, the computer must be powered by what is known as the “direct system” or by a “data shredder” tool that can be run by the system itself, and then the operating system – in which the computer is running – is not located on the hard disk but on the flash memory unit. Or a DVD.
This method is followed with traditional hard disks equipped with magnetic disks, “HDD” (HDD), while still-state disks (SSD) – which work with memory chips – require a different method, where the safe delete command must be executed here. Secure Erase via SSD management software from the company producing the hard disk, in order to perform the data removal process safely.
Instead, the Federal Office for Data Technology Security advises the use of “Parted Magic” that can also be used to recover data.
On the other hand, Bellmer pointed out that data can be cleaned from smartphones easily, as data is stored in an encrypted form on all devices in the last 4 or 5 years, and no one can access it without a user account, and this applies at least to iPhones. Starting with the operating system “iOS 8” (IOS 8), as well as the Android operating system since the sixth version.
Google has allowed companies through the release of “Android 10” the ability to activate the encryption option already through factory settings.
Despite the availability of tools for writing over data for smartphones, Bellmer emphasized that factory settings are usually sufficient, and the memory card must be removed from the smartphone before selling it or disposing of it if it is in it.
Destroy the data medium
If the user wishes to hand over his old computer or hard disk to the electronic equipment collection and recycling centers, he can remove the data by physical means by destroying the data medium.
The technology portal “Hays Online” confirmed that this method is more effective, as data can be removed by hammering the hard disk, and the hard disk can be removed from desktop or laptop computers easily.