Error message when you try to install Windows Vista Service Pack 2: "One or more system components that the service pack requires are missing"

To resolve this problem, use genuine Microsoft software media to reinstall Windows Vista with Service Pack 1 and then install Windows Vista SP2.

Reinstalling Windows on a computer that is running a retail version of Windows Vista

If you purchased a retail copy of Windows Vista, you can reinstall Vista from the Vista installation DVD.

Important The following steps are recommended for advanced computer users. If you are a beginning user or do not feel comfortable reinstalling Windows, you might want to ask help from a friend or contact Microsoft for support. For more information, see the How to obtain Windows Vista service pack support section in this article. There are two options for fixing this problem:

• An in-place upgrade to Windows Vista
• A clean reinstall of Windows Vista

With both options, you should backup your personal data to an external source. You should also note and find any special drivers or software that is required to use hardware devices such as video cards or printers.

Option 1: Perform an in-place upgrade to Windows Vista

Use the Windows Vista installation DVD to perform an in-place upgrade. An in-place upgrade keeps as much of your personal data and settings as possible.

Warning Before you perform an in-place upgrade, you should be prepared for a worst case scenario that results in your existing data on your computer being deleted. This data includes personal data, settings, hardware driver information, and software programs. If a worst case scenario occurs, you may have to reinstall all programs. Make sure that you back up personal data to disks or to other external storage devices before you perform an in-place upgrade. To perform an in-place upgrade, follow these steps.

Note It might help if you print these steps before you perform them. Also, be aware that it could take a few hours to complete these steps.

1. Start the computer.
2. Insert the Windows Vista DVD into the DVD drive and then close the drive tray. Wait for the Setup program to start automatically.
3. If the Setup program does not start automatically, click Start , type
   Drive:\setup.exe in the
   Start Search box, and then press ENTER.
   
   Note In this step, Drive is the drive letter of the computer’s DVD drive.
4. When the "Install now" screen appears, click
   Install now.
   
   Note When you receive the Get important updates for installation message, do not click Go Online.
5. Click Upgrade when the Which type of installation do you want screen appears.
6. Follow the instructions to install Windows Vista.
7. If Windows Vista is now running on your computer, you have completed the upgrade to Windows Vista.

After the upgrade has completed, you have to activate your copy of Windows Vista.
For more information about how to activate Windows Vista, click the following article number to view the article in the Microsoft Knowledge Base:

Option 2: Perform a clean reinstall of Windows Vista

Warning When you perform a clean installation, you may chose to format your drive. If you format your drive, existing data on your computer is deleted. This data includes personal data, settings, hardware driver information, and software programs. After you install the operating system, you must also reinstall all programs. Before you perform a clean installation, even if you do not format your hard driver, you should make sure that you back up personal data to disks or other external storage devices first. For more information about how to reinstall Windows Vista, click the following article number to view the article in the Microsoft Knowledge Base:

Reinstalling Windows on a computer that is running a preinstalled (OEM) copy of Windows Vista

If your computer has a preinstalled (OEM) copy of Windows Vista, and you receive this error, you should contact the manufacturer if you need help resetting your computer to the original factory defaults. Resetting your computer to the original factory defaults should also restore any system components that are needed to install the service pack.

You should back up any personal data before you contact the OEM for help. Using OEM recovery disks can sometimes cause data loss.

For more information about how to contact your OEM, please see the documentation that was included with your computer.