Reset Network Settings:

NOTE: By resetting network settings, all your saved Bluetooth and Wi-Fi networks will be deleted, and data restrictive settings, network selection mode, and background sync settings will be restored to default values.

  1. Open “Settings
  2. Go to “General Management” and tap “Reset
  3. Tap “Reset network settings
  4. If the phone is protected by a lock screen, enter your password/PIN to proceed
  5. Tap “Reset settings

Soft Reset Using Hardware Keys:

NOTE: A soft reset simulates battery removal, and this can be useful if the phone is frozen or unresponsive. By soft resetting the device no personal data stored on the phone’s memory will be deleted.

  1. Press and hold “Power” and “Volume down” simultaneously
  2. Keep both buttons pressed for about 45 seconds
  3. After the phone finishes rebooting, release both keys

Hard Reset

WARNING! By hard resetting the phone, all your personal data located on the internal memory, such as media files and ringtones, downloaded content, contacts, apps etc. will be deleted. However data located on the SD and SIM cards won’t be affected

NOTE: Before you reset the device, you can visit this thread for a guide on how to back up data, and this thread for a guide on restoring data.

Hard Reset via Settings:

  1. Launch “Settings
  2. Access “Sound and accounts
  3. Tap “Backup and restore
  4. Optionally, enable or disable “Back up my data” and “Restore
  5. Go back to “Settings” and access “General management
  6. Tap “Reset” > “Factory data reset
  7. Tap Reset device” and enter your lock screen PIN/password if necessary
  8. Tap “Continue” > “Delete all

Hard Resetting via Recovery:

NOTE: If your phone freezes, crashes, or otherwise prevents you from resetting it using the method above, alternatively you can try resetting the phone from the Android Recovery menu.

  1. Ensure the phone is powered off
  2. Press and hold “Volume Up” and “Home” at the same time, then press and release “Power
  3. At the Android screen, release the buttons and wait for the Android Recovery menu
  4. While in Recovery, press “Volume down” repeatedly to navigate the menu and highlight “Wipe data/factory reset
  5. Press “Power” again
  6. Highlight “Yes – delete all user data” and confirm
  7. Once done, ensure “Reboot system now” is highlighted and press “Power” one last time

See More: Samsung Galaxy C8: Soft/Hard Reset via Settings or Recovery