Hard reset Galaxy S I8520 Wifi 5.0

Samsung I8520 Galaxy S Wifi 5.0 hard reset

Turn off Galaxy Wifi. Press and hold Volume UP + POWER on the Galaxy S Wifi 5.0. When Samsung logo appeares release power but keep pressing Volume UP until you see android and then the recovery menu. Select wipe data/factory reset with Volume down and confirm with center Home/OK button.
Note: It will delete forgotten unlock pattern. It will not delete forgotten PIN code. You need to reflash its firmware.

Try Samsung Kies software to upgrade Samsung Galaxy S Wifi 5.0 YP-G70CW firmware
In Idle mode, open the application list and select
Settings → Privacy → Factory data reset → Reset phone → Erase everything. All data will be lost!

Samsung YP-G70 I8520 Galaxy S Wifi 5.0 soft reset

If your device freezes or hangs, you may need to close programs or reset the device. If your
device is frozen and unresponsive, press and hold [POWER] for 8-10 seconds. The device will reboot automatically.

Samsung I8520 Galaxy S Wifi 5.0 Download mode:

Turn Galaxy S Wifi 5.0 off. Press and hold Volume DOWN + Power buttons together.