Hard Reset SAMSUNG A551

First method:

  1. Go to Settings -> Privacy -> Factory data reset.
  2. Default values.
  3. After this device should be hardreseted.

Second method:

  1. Device must be turned on.
  2. Go to dialer.
  3. Tap this code: *2767*3855#
  4. After that device will restart.

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

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