Installing SP3 using Windows Update

If your computer is set to automatically install updates, you'll be prompted by Automatic Updates to install SP3. Follow the instructions on the screen. If you aren't prompted to install SP3, follow these steps:
To install SP3 using Windows Update

1.Click Start, click All Programs, and then click Windows Update.
2.Click Express (Recommended).
3.If your computer is up to date, Windows XP SP3 will be one of the updates that is automatically selected. Click Install Updates. If your computer isn't up to date, Windows Update will offer some other updates that you have to install first. Install those, and then repeat steps 1 and 2 to obtain Windows XP SP3.
4.Follow the instructions that appear on your screen.
5. After the installation is complete, click Finish to restart your computer.
6.If you disabled your antivirus software, enable it again.

Installing SP3 using Windows Update

Learn before you begin with widows XP3

Before you install SP3, we recommend you do the following:

*Log on to your computer using an administrator account, make sure all other users are logged off of the computer, and close all open programs.
*Back up your important files to an external location, such as an external hard disk, DVD or CD, or USB flash drive. For more information, see "Backing up files and folders" in Help and Support Center.
*If you're using a laptop computer, connect it to an AC electrical outlet and don't unplug or restart the computer during installation.
*If you have a third-party wireless network adapter, make sure that the device is supported by Windows XP SP3. For more information, go to the device manufacturer's website.
*If your computer is running Windows XP Professional, we recommend that you create an Automated System Recovery (ASR) set. This can help repair your system if the installation fails. For more information, see "To create an Automated System Recovery set using Backup" in Help and Support Center. (ASR isn't available for Windows XP Home Edition.)
*Some antivirus software might prevent SP3 from installing, or might slow down the installation. You can try temporarily disabling your antivirus software. If you do so, be sure that you're aware of the risks involved, and be sure to enable it after the service pack is installed.
*Make sure you have enough free disk space to install SP3 (even though much of that space will be reclaimed after the installation). If you need to create free disk space, see "Using Disk Cleanup" in Help and Support Center.

Amount of free disk space required to install SP3 (estimated):
Installation method

Approximate free disk space required
Windows Update
1,840 MB
Downloading SP3 from the Microsoft website
1,500 MB
Installing SP3 from a CD
1,765 MB

Learn before you begin with widows XP3