Why deleting is not wiping
Dragging files to the trash removes the listing, not the data, and free recovery software can pull back photos and documents from a drive that looks empty. A proper factory reset does the job on modern phones and most recent computers because their storage is encrypted by default. The reset throws away the encryption key, and what remains is unreadable noise.
The sequence for a phone or tablet
- Back up the device and confirm on another screen that the backup finished and contains your photos.
- Move your authenticator app and any two-factor codes to the new phone, because these do not always ride along in a backup.
- Unpair watches, earbuds and other accessories that are tied to the device.
- Sign out of the main account and turn off the find-my-device feature, which releases the activation lock.
- Remove the SIM card and any memory card, and erase the eSIM if the phone uses one and you are moving the number.
- Run the full erase option in settings, the one that removes all content and settings.
- Remove the device from the list of trusted devices in your account online.
Computers and hard drives
On a laptop, sign out of the operating system account, any app store and any software licensed per machine, then use the built-in reset option that removes everything and reinstalls the system. If the computer has an older spinning hard drive, or you are not sure the drive was ever encrypted, choose the reset option that fully cleans the drive. It takes hours rather than minutes and overwrites the data. A dead computer that cannot be reset still holds a readable drive, so pull the drive out and keep it or have it shredded.
The devices people forget
Printers store network passwords and sometimes copies of scanned documents. Smart televisions, streaming boxes, game consoles and smart speakers stay signed in to your accounts and your payment methods. A car you sell or return keeps your contacts, your garage door code and your home address in its navigation. Every one of them has a factory reset in its settings, and every one needs it.
Tip Write down the serial number before you hand the device over and keep it with the bill of sale, so you can prove later that the device left your hands and when.
