This is the step by step procedure on how to factory reset the LG Optimus S that clears all data and restore its original factory settings
However, this process may or may not delete data stored on the microSD memory card. We highly recommend to make a back up all of your personal data before you proceed.
Do and try this on the main home screen
1. From the main home screen, select Menu
2. select Settings, then the Privacy
3. select the Factory Data Reset
4. select Reset phone
5. Enter the password if prompted, then confirm by selecting Erase Everything
If the phone is frozen: Try a button combination
1. Turn the power off first. If your LG Optimus S is frozen, pull out the battery and reinsert it back again
2. Hold the Home and Volume Down button
3. Press and hold the Power button until the handset device turns ON
4. Just follow the on-screen instructions to reset the device
All data stored including the third-party applications installed will be deleted from the LG Optimus S. Once the restoration or wipe is complete, the phone will then reboot to its factory fresh default state settings.