What does Disk Boot Failure actually means

I have a system of Intel Core 2 Duo and 2 GB of Ram. It has a very long time gone when my first hard drive failed and my system does not start. But now again I am facing a similar kind of issue. I am getting a error saying Disk Boot Failure Press Ctrl + Alt + Del to restart. At first I had successfully formatted my computer and made things worked. But now the same is not happening at all. What does this error actually means. Is some files of Windows is getting misplaced. I am just looking for the exact explanation of this error. Does this is due to low ram.

The truth is that it never occur due to lack of ram. It appears when your system fails to read the hard drive. It is more related to the system hard disk. It only occurs if your hard drive is quiet old. Every system has its own bootable device which can be the hard drive of CD rom. The priority for the first boot device is given in the BIOS. So when the system fails to find the boot device then it pops up the error. This happens sometime when you remove your hard drive for sometime and put it back. It needs entire system formatting. There is no other way to fix that.

See this how all works. Whenever the computer system is started the BIOS searches for the boot device and initialize the operating system on that device. The hard drive of a computer system normally loads the operating system. As that is the only storage media. Now what happens sometime due to hardware issue or virus issue the hard drive is not able to load the operating system properly which causes this disk boot failure. You can try some number of restarts till you get final boot or else format your system.

In boot disk error the computer system is unable to load the operating system of any of the devices. Sometime the first boot device is set to Floppy and then message Disk Boot failure appears on the screen if the floppy disk contains no bootable file. Sometimes it is also possible to initialize the system and leave it at the command prompt. At the command prompt the computer can run on dos and from there it becomes possible to fix the corrupt mbr.