# Service Pack Installation - Knowledge Base

## 1. When I install Windows XP Service Pack 3 (SP3), it always fails. Why?

Windows XP Service Pack 3 installation will fail with the error **"Fatal Error during installation"**, if the patch KB925877 is installed on the target computer. You will need to uninstall the patch KB925877 prior to installing SP3.

- Use the **Install Software configuration** to uninstall the patch first (using a pre-installation script) and then install SP3.
- This procedure needs to be followed as the Patch Uninstall option is not available in the Service Pack Installation.

Follow the steps below to install Windows XP SP3:

1. Download the [uninstall_script_kb925877.txt](https://www.manageengine.com/products/desktop-central/uninstall_kb925877.txt) and rename it as `uninstall_kb925877.vbs`.
2. Add a software package for Windows XP SP3.
3. Specify the `uninstall_kb925877.vbs` as a pre-installation script. Do not specify any Exit Code.
4. Define an Install Software Configuration and deploy.