Can happen to anyone J It has happened to my friend so here is the solution how to recover and get back to your MAC Apple OS X computer.
- Locate your installation disk with OS X that came with your computer
- Insert the CD into drive and start up the computer and hold the C key pressed
- Once the Mac computer starts up, select Utilities > Reset Password
- Once the Reset Password window appears on your screen , chose the user account for which you want to reset the password
- Enter and verify a new password for the user, click Save
- Restart your Mac computer
- Once rebooted, you should be now able to logon with your new password
Here is very important note about this process. Changing password to logon to your MAC computer does not change password to access your keychain file. So if you do not recall the original password you won’t be able to use the saved login/passwords in keychain.
Go to your user folder/library/Keychains and move the login.keychain file out of the folder. Save this file somewhere under your documents in case you recall the old password and you can move it back and use again. For this moment, once you have moved out the login.keychain file, log out and log on and you will create a new empty login.keychain file that is associated with your login and you can now start use and building.
Once you recalled your old password, move back your old login.keychain file, log out and on, launch the Keychain Access and chose Edit > Change Password for Keychain login. You will be prompted for old and new password.