Before you buy a new cell phone or new tablet, please try the following procedure to repair your device. First charge your battery, backup your important data if possible and in most cases take out SIM and SD card before factory reset. It is impossible to recover your data after doing a hard reset, so online backup is always important. For all of your data, a backup should be done on an external device, hard drive, raid system or media. With or without insurance, if your cell phone lost, damaged or stolen at least your invaluable data is backed up in a safe place. If you are about to sell your phone and you want to wipe your personal data, or if your phone affected with virus you have to do a hard reset. In some cases, you can delete the forgotten password or lock pattern from your device as well. All information is for devices with stock based ROMs. If you are using rooted device, always back up your EFS folder first, containing your IMEI info, etc.!
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: Please note that this is only for firmware upgrade!
Turn Galaxy S Wifi 5.0 off. Press and hold Volume DOWN + Power buttons together.