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.

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

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