It is very important to remove the memory card from your smartphone or tablet before you begin, otherwise you could lose all your data.
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.
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