The product key is on a Sticker attached to the case of the computer and is a 25 Digit Alpha Numeric String of five lots of five characters. The M$ Install Disc will also need to be the same version of XP as is on the computer and you can use the COA Attached to this computers Case for the Product Key.
So if it had XP Home you'll need a XP Home Install Disc made by Microsoft, If it had XP Pro you'll need a XP Pro M$ Install Disc and if it had MCE you'll need a M$ Made MCE Install Disc. The M$ Install Disc will also need to be of the same type so if this computer previously had a 64 Bit Version of XP you'll need the same version a 64 Bit Install Disc.
What you need to do here is a Repair or Inplace Install to rewrite the deleted Files that you have removed. Follow these directions and you'll have the system working very quickly but you'll need to reapply all of the Service Packs and Hot Fixes that have been released since your Install Disc was made.
[i]How to perform an in-place upgrade (reinstallation) of Windows XP
View products that this article applies to.
Article ID : 315341
Last Review : January 28, 2008
Revision : 5.2
This article was previously published under Q315341
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INTRODUCTION
MORE INFORMATION
Before you perform a repair or an in-place upgrade
Troubleshooting
Internet Explorer 7
Data backup
Windows Installation CD
Device drivers
Programs
Network settings
Internet provider information
Startup sequence
Windows XP preinstalled
Windows XP Service Pack 2
Method 1: Reinstall Windows XP by using Windows XP
Method 2: Repair install of Windows XP by starting your computer from the Windows XP CD
After you perform an in-place upgrade
Reinstall all updates to Windows
Reinstall Internet Explorer 7
INTRODUCTION
This article describes how to perform an in-place upgrade (reinstallation) of Windows XP. This is also named a repair installation. It reinstalls Windows XP to the same folder. You may want to perform an in-place upgrade if your installation of Windows XP must be repaired. Such a repair installation may be required if one of the following conditions is true:? You cannot start Windows XP in safe mode.
For more information about how to start your Windows XP-based computer in safe mode, click the following article number to view the article in the Microsoft Knowledge Base:
315222 (http://support.microsoft.com/kb/315222/) A description of the Safe Mode Boot options in Windows XP
? You cannot start Windows XP after you install a Microsoft software update.
? There is a registry problem that cannot be solved by using other tools such as System Restore.
For more information about System Restore, click the following article number to view the article in the Microsoft Knowledge Base:
306084 (http://support.microsoft.com/kb/306084/) How to restore the operating system to a previous state in Windows XP
? You must apply default (file and registry) permissions to your Windows XP installation. This condition occurs because of missing or damaged program files after you make changes or updates to your computer or programs.
? You must register COM components and Windows File Protection (WFP) files. This condition occurs because of missing or damaged system files.
? You must use the Windows Setup program to enumerate Plug and Play devices again. This includes the hardware abstraction layer (HAL).
To reinstall Windows XP, use the appropriate method in the "More information" section.
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MORE INFORMATION
Note You may want to disconnect from the Internet during the installation. Disconnecting from the Internet during the installation helps protect you from malicious users. You may also want to enable the firewall in Internet Explorer.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
283673 (http://support.microsoft.com/kb/283673/) How to turn on or turn off the firewall in Windows XP
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Before you perform a repair or an in-place upgrade
Review the following topics before you perform a repair or in-place upgrade of Windows XP.
Troubleshooting
If you feel comfortable troubleshooting, consider the following Microsoft Knowledge Base articles before you perform a repair or an in-place upgrade:
308041 (http://support.microsoft.com/kb/308041/) Advanced troubleshooting for general startup problems in Windows XP
326841 (http://support.microsoft.com/kb/326841/) Support WebCast: Microsoft Windows XP: Troubleshooting Startup and Shutdown Problems
307654 (http://support.microsoft.com/kb/307654/) How to install and use the Recovery Console in Windows XP
Internet Explorer 7
If you have Internet Explorer 7 installed on your computer, you must uninstall Internet Explorer 7 before you perform a repair install or in-place upgrade.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
917964 (http://support.microsoft.com/kb/917964/) How to perform a repair installation of Windows XP if Internet Explorer 7 is installed
Data backup
Before you reinstall Windows, back up all data. Determine the data that you want to back up. This data may include the following:? My Documents (documents, pictures, music, videos)
? Favorites
? Address books
? E-mail messages
? Document templates
? Macros
? Boilerplates
Backup copies of your registry files (located in the %systemroot%\Repair folder) are replaced after an in-place upgrade is complete. The registry files in the Repair folder are either from the first time that you started Windows XP or the last time that you used the Backup utility to back up the system state. If you must use registry backups after the in-place upgrade is complete, copy these registry backups to another location before you perform an in-place upgrade.
Windows Installation CD
Before you perform a repair or in-place upgrade, have the Windows installation CD and the product key available. If you do not have the Windows installation CD and the product key available, you cannot reinstall Windows. If Windows was preinstalled on your computer, contact the manufacturer of your computer for help in locating or obtaining the Windows installation files and your product key.
Device drivers
Many of the device drivers for your hardware components are integrated into Windows. However, devices such as printers, monitors, graphic cards, sound cards, modems, external drives, and scanners usually have separate installation CDs. If you do not have all of the drivers for your hardware components, you can download the drivers from the Internet and then write them to a CD.
If your computer requires a third-party mass storage device driver or hardware abstraction layer (HAL), make sure that you have a copy of the files on a separate storage media before you perform a repair or in-place upgrade.
Programs
You should collect and store the CDs and product keys for your programs in an appropriate location so that you can reinstall the programs after you have reinstalled Windows. These programs may include the following:? Microsoft Office programs
? Antivirus software
? CD writing software
? Internet Provider software
Network settings
You can restore certain network settings after you reinstall Windows. If this step is required, record your computer's network settings. These settings include the following:? Computer name
? Workgroup or domain
? TCP/IP settings
Internet provider information
To make sure that you can reconnect to the Internet after you have reinstalled Windows, record your Internet provider information. This includes user name and password information.
Startup sequence
If it is required, adjust the BIOS startup sequence. The sequence should be in the following order:? CD drive
? Hard disk
? Floppy disk drive
Windows XP preinstalled
If your computer came preinstalled with Windows XP, before you follow the steps later in this article, view the following article in the Microsoft Knowledge Base:
312369 (http://support.microsoft.com/kb/312369/) You may lose data or program settings after reinstalling, repairing, or upgrading Windows XP
Windows XP Service Pack 2
If you have Windows XP Service Pack 2 installed on your computer, you must reinstall Service Pack 2 after you reinstall or repair Windows XP. To do this, see the appropriate method.
Note Service packs are cumulative. Each new service pack contains all the fixes that are included with earlier service packs and any new fixes. You do not have to install an earlier version of a service pack before you install the latest version. For example, you only have to install Windows XP Service Pack 2 (SP2), you do not have to install Windows XP Service Pack 1a (SP1a).? Method 1: Combine the Service Pack 2 files together with the Windows XP setup files
Combine the Service Pack 2 files together with the Windows XP setup files.
For more information about combining Windows XP with Service Pack 2 for reinstallation, click the following article numbers to view the articles in the Microsoft Knowledge Base:
894947 (http://support.microsoft.com/kb/894947/) Combining Windows XP with Service Pack 2 for reinstallation (Part 1: Introduction)
894948 (http://support.microsoft.com/kb/894948/) Combining Windows XP with Service Pack 2 for reinstallation (Part 2: Copying the Windows CD to the hard disk)
894949 (http://support.microsoft.com/kb/894949/) Combining Windows XP with Service Pack 2 for reinstallation (Part 3: Integrating Service Pack 2 in the Setup files)
894950 (http://support.microsoft.com/kb/894950/) Combining Windows XP with Service Pack 2 for reinstallation (Part 4: Reading the boot image file)
? Method 2: Obtain the service pack CD and reinstall the service pack after you reinstall Windows XP
To order Windows Service Pack 2 on CD, visit the following Microsoft Web site:
http://www.microsoft.com/windowsxp/downloads/updates/sp2/cdorder/en_us/default.mspx (http://www.microsoft.com/windowsxp/downloads/updates/sp2/cdorder/en_us/default.mspx)
? Method 3: Download the service pack after you reinstall Windows XP
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
322389 (http://support.microsoft.com/kb/322389/) How to obtain the latest Windows XP service pack
System Restore
If you perform an in-place upgrade of Windows XP, all existing restore points are removed and a new system checkpoint restore point is created after the in-place upgrade is complete. Do not perform an in-place upgrade if you may have to use System Restore to restore your computer to a previous state.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
301224 (http://support.microsoft.com/kb/301224/) System Restore "restore points" are missing or deleted
Repair a component
Do not perform a repair or in-place upgrade to repair a component or program that is currently not installed. If you have the necessary permissions, use the Add or Remove Programs item in Control Panel, or reinstall the component or program instead of Windows. To open Add or Remove Programs in Windows XP, click Start, click Control Panel, and then click Add or Remove Programs.
User account problem
Do not use a repair or in-place upgrade to try to resolve a problem with a user account, password, or local profile. To determine whether the problem is related to a user account, password, or local profile, create another user account (if you have the required permissions), and then log on to that account to see whether the problem is resolved.
For more information about creating a new user account in Windows XP, click the following article number to view the article in the Microsoft Knowledge Base:
279783 (http://support.microsoft.com/kb/279783/) How to create and configure user accounts in Windows XP
Third-party programs
Do not use a repair or in-place upgrade to resolve a problem with third-party programs, files or registry entries. Contact the manufacturer of the third-party program to resolve any problems.
Disk problems
Do not use a repair or in-place upgrade if you suspect disk problems.
For more information about checking for disk errors, click the following article numbers to view the articles in the Microsoft Knowledge Base:
315265 (http://support.microsoft.com/kb/315265/) How to perform disk error checking in Windows XP
308041 (http://support.microsoft.com/kb/308041/) Advanced troubleshooting for general startup problems in Windows XP
You can also contact the computer manufacturer for more information about how to troubleshooting hard disk problems.
Third-party devices
Do not use a repair or in-place upgrade if you suspect a problem with a third-party device. Determine whether the latest device drivers are currently installed for the device. Contact the manufacturer of the third-party device to resolve any problems.
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Method 1: Reinstall Windows XP by using Windows XP
To reinstall Windows XP by using Windows XP, follow these steps: 1. Start your computer.
2. Insert the Windows XP CD in your computer's CD drive or DVD drive.
3. On the Welcome to Windows XP page, click Install Windows XP.
4. On the Welcome to Windows Setup page, click Upgrade (Recommended) in the Installation Type box (if it is not already selected), and then click Next.
5. On the License Agreement page, click I accept this agreement, and then click Next.
6. On the Your Product Key page, type the 25-character product key in the Product key boxes, and then click Next.
7. On the Get Updated Setup Files page, select the option that you want, and then click Next.
8. Follow the instructions that appear on the screen to reinstall Windows XP.
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Method 2: Repair install of Windows XP by starting your computer from the Windows XP CD
To reinstall Windows XP by starting your computer from the Windows XP CD, follow these steps: 1. Insert the Windows XP CD into your computer's CD drive or DVD drive, and then restart your computer.
2. 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.
Note Your computer must be configured to start from the CD drive or DVD drive. For more information about how to configure your computer to start from the CD drive or DVD drive, see your computer's documentation or contact your computer manufacturer.
3. You receive the following message on the Welcome to Setup screen that appears:
This portion of the Setup program prepares Microsoft Windows XP to run on your computer:
To setup Windows XP now, press ENTER.
To repair a Windows XP installation by using Recovery Console, press R.
To quit Setup without installing Windows XP, press F3.
4. Press ENTER to set up Windows XP.
5. On the Windows XP Licensing Agreement screen, press F8 to agree to the license agreement.
6. Make sure that your current installation of Windows XP is selected in the box, and then press R to repair Windows XP.
Note If Windows XP was preinstalled on your computer, and you do not have the Repair option, contact your computer manufacturer to make sure that you have the installation CD for a repair install.
7. Follow the instructions that appear on the screen to reinstall Windows XP. After you repair Windows XP, you may have to reactivate your copy of Windows XP.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
310064 (http://support.microsoft.com/kb/310064/) How to troubleshoot Windows XP Setup problems when you upgrade from Windows 98 or Windows Millennium Edition
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After you perform an in-place upgrade
After you perform an in-place upgrade or repair installation, you must reinstall all updates to Windows. To reinstall Windows updates, visit the following Microsoft Web site:
http://windowsupdate.microsoft.com (http://windowsupdate.microsoft.com)
Reinstall all updates to Windows
After you perform an in-place upgrade or repair installation, you must reinstall all updates to Windows. To reinstall Windows updates, visit the following Microsoft Web site:
http://windowsupdate.microsoft.com (http://windowsupdate.microsoft.com)
Reinstall Internet Explorer 7
When Windows XP has been repaired and is running correctly, reinstall Internet Explorer 7. To reinstall Internet Explorer 7, you must have the Internet Explorer 7 installation package. This installation package may still be on the computer from the first time that you installed Internet Explorer 7. Locate the installation package in the folder in which you saved the files.
Note This package may be located in the Temporary Internet Files folder. If you cannot locate the Internet Explorer 7 installation package, visit the following Microsoft Web site to obtain this package:
http://www.microsoft.com/windows/ie/downloads/default.mspx (http://www.microsoft.com/windows/ie/downloads/default.mspx)
To connect to the Microsoft download site, you must have a functional Web browser. If Internet Explorer 6 does not work on the computer after you uninstall Internet Explorer 7, you cannot download the Internet Explorer 7 installation package. Therefore, you will have to use a computer that has a functional Web browser to download the Internet Explorer 7 installation package. Then, use a shared network drive to install the program from the downloaded installation package on this other computer onto the repaired computer. If you cannot use a shared network for this purpose, copy the Internet Explorer 7 installation package onto a CD on the second computer. Then, use this CD to install Internet Explorer 7 on the first computer. [/i]
Full M$ Knowledge Base Article is located here
http://support.microsoft.com/kb/315341
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