How to unlock my computer i forgot my password

I don't know which operational system your computer installed with.
For different Windows OS, there are suitable ways to unlock the computer. Or what preparation you make for before your computer locked.
For example, you can access Windows XP in safe mode. Unlock computer in safe mode is effective way.
If you have a password reset disk, reset windows 7 with boot disk is another choice.
So how to unlock computer or laptop based on the Windows operational system and what you have.
More details, you can refer to:
http://www.isunshare.com/windows-password/unlock-laptop-when-forgot-password.html

You can try following methods to unlock your computer:-
1) Use password reset disk.
2) Using other available administrative account.
3) Reset Windows 7 password by third party software.
If still the issue persists then you can also take tech support from AskPCExperts. To know more you can visit: http://www.askpcexperts.com

You can create a Windows password reset bootable CD/DVD or USB flash drive to reset forgotten Windows password, i have created a bootable USB flash drive with the tool Windows Password Breaker and reset my administrator password successfully.