1. Put your hard disk of your computer in any other pc .
2. Boot that computer and use your hard disk as a secondary hard disk (Don't boot as primary hard disk ).
3. Then open that drive in which your windows is installed.
4. Go to location windows->system32->config
5. And delete SAM.exe and SAM.log
6. Now remove hard disk and put in your computer.
7. And re-boot your computer
