I am having this strange problem with my PC.Whenever i turn on my computer, windows is not booting.I mean the screen remains blank all the time.It seems to be like a hard disk fail bcoz its led is also not glowing.
Also the led on the keyboard is also not glowing.But the fan inside the CPU is working fine.That means, power supply is present in it.
What can be the prob?
Help me please.

Could possibly be a hard drive problem. I had a similar problem. Do you get any error messages, such as hard disk boot failure or no system disk?

Actually, it sounds like it might not even be getting that far. Nisar, do you literally mean there is nothing at all displayed on the screen from the point that you switch it on? And, presumably, there's no beep from the system speaker? Sounds like it's not POSTing.

Yes DJ it was the exactly what you are referring to.But then i had it checked and replaced one component from the motherboard.
Then during booting, i got a msg similar to as owen said saying - "Error loading OS".
So there were problems in both motherboard and hard disk.So i had to purchase a new one.Now its fit and fine.Thanks for replying.