What have to do if WinXP won’t boot?

When your computer hardware appears to power up okay, but the Windows XP operating system won't boot properly, you have to begin a troubleshooting expedition that includes getting into the operating system, determining the problem, and then fixing it. To help you get started on this expedition, here are few things you can do when Windows XP won't boot.

1. Bypassing Windows with the Recovery Console
When a Windows XP boot problem is severe, you'll need to use a more drastic approach. The Windows XP CD is bootable and will provide you with access to a tool called Recovery Console.
Solving Startup Problems with the Recovery Console

- Use a recovery console
- fix a corrupt boot.ini
- fix a corrupt master boot record
- disable auto restart
- restore from a backup

NOTE The Recovery Console can be a powerful tool for finding and fixing certain types of startup problems, but if you don’t know exactly what you’re doing, it can also allow you to create new problems that will complicate the ones that are already on your computer or even completely trash Windows’ ability to start. Therefore, it’s best to use the Recovery Console only when you have detailed instructions for performing a specific task from a reliable source such as the Microsoft Knowledge. The best way to load and use the Recovery Console is to run it directly from the Windows XP CD. To do so, follow these steps:

1. Place the Windows XP CD into the drive.
2. Restart the computer from the CD.
3. At the Welcome to Setup screen, press the R key. The Recovery Console starts and shows a list of Windows installations on your computer. In most cases, there will be just one item in the list.
4. Enter the number of the version you want to use, and press the ENTER key. The Recovery Console will ask for the administrator password.
5. Type the same password you would normally use to log into Windows as an administrator, and press ENTER. If there is no administrator password, just press the ENTER key. When the Recovery Console accepts the password, it will display a C:\WINDOWS> prompt. To close the Recovery Console, type Exit at the C:\ prompt.

2. Perform in Place Upgrade
If you can't repair a Windows XP system that won't boot and you don't have a recent backup, you can perform an in-place upgrade. Doing so reinstalls the operating system into the same folder, just as if you were upgrading from one version of Windows to another. An in-place upgrade will usually solve most, if not all, Windows boot problems.