I did repair my pc by formatting and installed windows 7 ultimate x64. It would be funny of hearing the cause of the problem- Directly switched off the pc, I mean the plug point switch. I don't even have a Ups to save my pc. And it was done by my grandmother. This is the most imporatnt point of the cause. Hahaha.
Note- Don't let people whose in excess of age or small childern to handle electronic appliances. Even we can trust the children but not the elders. Please guide them and save your things. This article was written By an affected human being and it is also for a time pass.