Ensure the "Archive Files" option is selected. This allows you to uninstall SP3 if something breaks.
Antivirus or file permission issue. Fix: Disable all security software. Run the installer as Administrator. If still failing, boot into Safe Mode (F8 at startup) and run the installer there. how to upgrade windows xp sp2 to sp3 without formatting
A: Yes, as long as you did not delete the $NtServicePackUninstall$ folder. Go to Add/Remove Programs → Windows XP Service Pack 3 → Remove. Ensure the "Archive Files" option is selected
Remember that Windows XP is no longer supported by Microsoft. Even with SP3, avoid connecting it to the internet. Use it for offline tasks, legacy hardware control, or vintage gaming. And always keep a recent backup. legacy hardware control
Then retry the SP3 install.