WARNING! When you master reset your phone all personal data stored on the internal memory will be lost, including downloaded content, ringtones, contacts, apps etc. Furthermore all settings will be restored to factory values.
NOTE: Before proceeding with the factory reset you can visit this thread for a guide on how-to backup data on the Galaxy J7, or this thread for a guide on how-to restore data.
Master Reset via Settings:
- Open the apps drawer
- Go to “Settings”
- Scroll to “User and Backup”
- Tap “Backup and reset”
- Optionally clear the boxes associated with “Automatic restore” and “Back up my data”
- Tap “Factory data reset” > “Reset device”
- In case your phone is protected by a PIN, password or pattern, enter it and tap “Continue”
- Lastly, confirm by pressing “Delete all”
Master Reset via Recovery:
NOTE: In case your phone prevents you from resetting it via settings, you can alternatively try resetting it through the recovery menu, which can be accessed by performing a combination of button presses.
- Turn off the phone
- Press and hold “Home”, “Volume Up”, and “Power” at the same time
- After the phone vibrates, release “Home” and “Power” but continue holding “Volume Up”
- When you see the “Android System Recovery” menu, release all hardware buttons
- From the recovery menu press “Volume down” repeatedly until you highlight “wipe data / factory reset”
- Press “Power” to select the highlighted option
- Press “Volume Down” and highlight “Yes – delete all user data”
- Press “Power” and wait for the phone to reset
- Once done, “Reboot system now” should be highlighted
- Press “Power” to reboot your device