Hard Reset SAMSUNG i637 Jack

First Method:

  1. On the Home screen, select Start ➔Settings➔Security➔Master Clear and press the Confirm  center key.
  2. Press the Yes soft key to confirm. The phone resets and reboots itself.

Second Method:

  1. While the phone is off, power on the phone while holding the 5/F key.
    HardReset SAMSUNG i637 Jack
  2. The Format Menu displays.
  3. Press  Master Reset.

Hard Reset will erase all of your data
All described operations you are doing at your own risk.

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