Recover Lock Combination HELP! How Do I Recover A Password That I Set A While Ago That Locks My Whole Computeer?

HELP! how do I recover a password that I set a while ago that locks my whole computeer? - recover lock combination

Some time ago I have a password, not to start the way users log on and off.I so I change again. I wanted to change again, and I did it without me. Closed my passwords were all the same, but obviously I have this differently.Theres any way, and none of my overalls.