It is very important to remove the memory card from your smartphone or tablet before you begin, otherwise you could lose all your data.
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Make sure the phone is switched off and the battery charged to 100%. There are several ways to enter the Android system recovery mode. Depending on the model of your device, try the following combinations:
- Power button + Volume up button
- Power button + Home button
- Volume down + Power button
- Power button + Volume down + Volume up
Once in the Android system recovery menu, select « wipe data/factory reset » then « Yes delete all user data », your device is now brand new.
hard reset android device,