Samsung I9003 Galaxy SL hard reset
Turn off your phone. Press vol up power + home key together. Select wipe data.
Turn off your phone. Press VOL UP + HOME + POWER for 5 sec, then leave POWER and continue the other two buttons, till u see yellow text.
Now in recovery mode select WIPE DATA/Factory Reset... and then, YES.
Use this method to hard reset your Samsung GT-I9003 Galaxy SL phone: Enter *2767*3855#. Warning! All your data including contacts, messages etc. will be lost! Copy all your necessary data/Contacts/Messages etc. to SIM or make backup on your PC before full reset!
Go to Menu > Settings > Privacy > Factory data reset: Reset your settings to the factory default values.
Your device freezes or has fatal errors 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 [POWER key] for 8-10 seconds. The device will reboot automatically.
If this does not solve the problem, perform a factory data reset. In Idle mode, open the application list and select
Settings → Privacy → Factory data reset → Reset phone → Erase everything.
If you know the hard reset using buttons / keys, pls leave a comment. All comments are welcome! :)