We can use single method to unlock or hard reset samsung glaxy s1 ans glaxy s2. If mobile gives bad performance or you have forgot pattern lock then we can reset device to factory default settings via key combination known as hard reset. This is best option in android phones for every one to solve any software related problem. Screen pattern lock is security option in android smartphones to safe mobile data from unauthorised access. Always take backup of important data before hard reset mobile, because this trick will remove all data on mobile memory, and there are less chances to get back mobile data. Before applying pattern lock first add google account via settings, after adding google account you can recover password with google account without losing any thing on mobile memory. Lets start the procedure...
Remove battery or turn off mobile.
Press and hold Volume Up + Home + Power button together.
When device reboot release these three buttons.
Android system recovery manu will appear.
Use volume up and down keys to scroll through the manu.
Select wipe data/ factory reset and press home button to confirm selection.
Scroll down and select yes_ _ _ delete all user data and press home to confirm.
When formatting complete press home key to system reboot.