- 1). Click the Windows "Start" menu and click "Run." Launch the programs window by typing "appwiz.cpl" (without quotes) and pressing Enter.
- 2). Display the Windows XP updates by clicking the "Show updates" check box located on the top of the programs window. Scroll down, click "Service Pack 3," and click "Remove." When prompted, confirm that you want to uninstall the Windows update from your computer. The uninstaller removes SP3. When the process completes, restart your computer.
- 3). Click the Windows "Start" menu, click "All Programs" and click "Windows Update" to launch the updating tool. Click "Express (Recommended)" If you have all the other updates other than Service Pack 3, click "Install Updates." If Windows prompts you to install other updates before installing Service Pack 3, follow the guided prompts to do so.
- 4). Click "Finish" after the installation completes and restart your computer.
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