Computer boots like normal, Windows loading screen will appear, after a few seconds, a quick blue screen will appear and then your computer restarts. You can't even read the BSOD information because it just flash in less than a second. This will go on and on and you will be stuck in a loop. Computer will not boot even in safe mode or any other option.
First thing to do is to disable the option that computer automatically restarts when a fatal error/system failure occurs. There is an option inside windows for that, but in this case we can't do that. So what you need to do is to press F8 before the Windows XP logo appears right after the BIOS screen (just like what you do when you want to boot in safe mode). This screen will appear:
(this image is from Vista but it's basically the same) What you need to do is choose the option: "Disable automatic restart on system failure" (the one in the red box). After doing that, your computer will restart, and you will now see the Blue screen error message.
9 out of 10 computers that i worked on will show the BSOD (blue screen of death) message:
For some, the only solution when you see this error is to reformat the hard drive. But this problem can be easily repaired by using the built in Window Tool "Chkdsk" or checkdisk (same as scandisk on older windows version).
What you need is a Windows XP installer CD, put in you CD Drive, boot your computer from it.
When this screen appear, choose the Repair option:
You will now get to the command prompt. . Type chkdsk /p and hit Enter. This will launch a utility which will check for errors on your hard drive, it will take a while, just be patient. When it is finished, remove the installation disk on your cd rom drive, type EXIT and your computer will now be back to normal.