Samsung ATIV S NEO hard reset1. You must have enough battery life.
2. Turn off the phone.
3. Press the Volume Down Key + Power Key to turn on the device
4. After the vibrator goes, still hold the volume down key, but release the Power Key.
5. Wait for the startup screen booting with an exclamation mark " ! " then release the volume down key.
6. Press the following buttons in the following order: volume up , Volume down, Power key, volume down.
7. Wait a moment, a message such as loading new software will start the hard reset process
or reset Samsung sph-i800 in menu settings
Resetting Windows Phone 8 RT mobile phone, reset samsung sph-i800, Samsung SPH-I800
If your device freezes or hangs, you may need to close programs or reset the device to regain functionality. If your
device is frozen and unresponsive, press and hold the Power key for 11-13 seconds. The device will power off forcefully.
If this does not solve the problem, perform a factory data reset. In Menu mode, select Settings → system → about →reset your phone → yes → yes.