you proceed flashing / hard resetting your phone / tablet make sure
to back up your important files if possible. Because we care about
We also suggest that your battery should be atleast 50% or better to have it fully charge, lower than the said value may cause unwanted result, such as bricking your phone / tablet rendering it unuseable. This is very important in flashing your phone / tablet. Use original USB cable as possible.
Files that you downloaded should not be corrupted, if ever the file is corrupted you might brick your phone. Or the flashing will start.
Drivers are very important specially in Spreadtrum Chipset, having an Spreadtrum SPD6610 (non android devices) driver will not work in SPD6820 (android devices).
If you are using laptop to flash your phone, make your that it has enough charge. If your laptop shutdown when your flashing your phone/tablet, you'll end up bricking your phone. Sometimes you can still recover your phone just flash it again and your phone will boot up again. But that is just a case to case basis, if your phone / tablet is deadboot (totally dead, erased all program in the chip) you can't recover it, you will need to seek professional help (technician).
In this tutorial I will teach you how to hard reset your Nokia Lumia 520. This can also fix the cog wheel of death, blue screen of death. Hard reset combination works in other Windows Phone 8 devices.
OK Let's proceed follow the instruction bollow
1. Turn the power Off.
2. Press and hold the Volume down and connect the charger or the USB cable with PC, for about 8 seconds, you will see an exclamation mark (!) on the screen. Note: If you do not press any of the following keys, then the phone wp8 will starts boot normally.
Then press the keys in this exact order:
1. Volume up
2. Volume down
4. Volume down
Then wait until the phone reboot. Just be patient. It takes about 2-3 minutes until it reboot into normal state.