I have pressed Volume up, Home and Power button, but it's only making the phone to go off. What should I do to unlock my Samsung GT S-5301?
There is a trick with these phones. You have to keep the buttons pressed until the Samsung logo appears, then immediately release the buttons, and the Android logo should appear.
For erasing instructions, consult the following question where a more in-depth answer is provided. : http://answers.informer.com/137228/unlock-samsung-5301-when-forgot-google-details-and-backup-pin