This is a very basic piece of information but I get asked it a lot and maybe it can help some folks. One of the best kept secrets of Windows XP is it's built in repair feature!
In previous versions of Windows, correcting an operating system error, or installing a new motherboard, usually meant formating and reinstalling, resulting in loss of all data. Don't worry; Windows XP repair feature won't delete your data, installed programs, personal information, or settings. It just repairs the operating system!
Note: The system repair function will remove any updates you have previously installed that are not included on the CD.
Drivers will also be reverted to their original XP versions, as well as some settings (network & performance settings may sometimes be reset to their defaults). It may be necessary to reactivate your Windows XP as well. When finished, you will have to download all of the updates from Microsoft Windows Update, because they are all replaced during repair.
Why would I want to reinstall Windows XP? 1) Can't start Windows XP in safe mode. 2) You have problems caused by a recently installed system update (Windows Update, hotfix, Windows XP service pack, or Microsoft Internet Explorer update). 3) Your problems can't be solved with system restore, or you can't access system restore. 4) You've installed a new motherboard, or made other major hardware changes and need to reinstall Windows.
Let's get started! Step 1: Rule out hardware issues. Windows Repair will only fix software problems. Hardware issues can also cause boot problems (i.e. bad hard drive, memory, CPU, or power supply).
Step 2: Backup. It's always a good idea to backup your important data before making changes to Windows XP. Relax, if you follow these instructions your data will be perfectly safe.
Step 3: Boot from your Windows XP CD. Insert the Windows XP CD into your computer's CD-ROM or DVD-ROM drive, and then restart your computer. When the "Press any key to boot from CD" message appears on the screen, press a key to start your computer from the Windows XP CD. Can't boot from your CD? Please see the note at the bottom of this page (Configuring Your Computer to Boot from CD).
Step 4: A blue screen will appear and begin loading Windows XP Setup from the CD. Note: RAID/SCSI/Unsupported UDMA users: You will be prompted to "press F6 to install any third party SCSI or RAID drivers". Most users will not have to press F6, but if you are running RAID, SCSI or unsupported UDMA controllers, then you will have to have your controller drivers on a floppy disk. If you are unsure whether you have RAID/SCSI, then simply let the CD load without pressing F6.
When completed loading files, you will be presented with the following "Windows Setup" screen, and your first option. Select "To set up Windows XP now, press ENTER". DO NOT select Recovery Console. Press enter to continue and F8 to accept the EULA. Next, Windows Setup will find existing Windows XP installations. You will be asked to repair an existing XP installation, or install a fresh copy of Windows XP. If no installations are found, then you will not be given the option to repair. This may happen if the data or partition on your drive is too corrupted. Note: If you install a fresh copy, all data on that partition will be lost!
Your almost finished! Windows XP will appear to be installing itself for the first time, but it will retain all of your data and settings. Just follow the prompts, and have your CD-KEY ready if needed.
Do you have more than one system, or lost your CD-KEY? Visit the keyfinder page to retrieve your CD-KEY. Due to the proliferation of the Blaster and Welchia Worm/Virus be aware that a Repair Install will leave your system vulnerable. You can get infected within seconds. Do not go on line until you have enabled XP's firewall first. Remember to run Windows Update! (install critical updates first) A repair install will work on Home as well as Pro.