Minimizing XP SP3 woes - UPDATED

I'm getting sporadic reports of Windows XP users having problems installing XP SP3 on some systems. Here are some tips to help make the install process a little smoother.

• Disable AV software It seems that some antivirus (AV) software causes the SP3 install to hang, while the installer seems fine with others. Disable AV software before beginning the install process.
• Uninstall beta/RC versions of SP3 It's a good idea to get rid of these earlier versions. If you're having problems removing them, try ininstalling previous versions through Safe Mode.
• Uninstall IE8 SP3 won't play nicely on systems that have IE8 installed.
• Update drivers Might help, especially if your system is running really old drivers.
• Disable unnecessary startup applications It's not just AV software that can cause SP3 problems. If you're having problems getting SP3 to install then disabling as many unnecessary startup applications as you can might help.
• Possible solution to endless reboots Win dows blogger Jesper Johansson offers some advice for thiose suffering endless reboots when trying to install SP3.

I've only come across one stubborn system personally and disabling the AV software seemed to fix the problem.

If you are getting any of the following errors then this page on the Microsoft KnowledgeBase site might help:

• Service Pack 3 Setup Error You do not have enough free disk space on %SystemDrive% to install Service Pack 3.
• Service Pack 3 Setup Error You do not have enough free disk space on %SystemDrive% to archive the uninstall files.
• Service Pack 3 setup error. Access is denied.
• Service Pack 3 setup error. Service Pack installation did not complete
• You do not have permission to update Windows XP. Please contact a system administrator.
• Digital Signature Not Found The Microsoft digital signature affirms that software has been tested with Windows and that the software has not been altered since it was tested. The software you are about to install does not contain a Microsoft digital signature. Therefore, there is no guarantee that this software works correctly with Windows. Name of software package If you want to search for Microsoft digitally signed software, visit the Windows Update Web site at http://windowsupdate.microsoft.com to see if one is available. Do you want to continue the installation?
• Microsoft Windows The signature on the software package you want to install is invalid. The software package is not signed properly.
• Name of Update Package The cryptographic operation failed due to a local security option setting.
• Name of Update Package Setup could not verify the integrity of the file Update.inf. Make sure the Cryptographic service is running on this computer.
• Failed to install catalog files.
• The software you are installing has not passed Windows Logo testing to verify its compatibility with Windows XP. (Tell me why this testing is important.) This software will not be installed. Contact your system administrator.
• The software you are installing has not passed Windows Logo testing to verify its compatibility with this version of Windows. (Tell me why this testing is important.)
• Service Pack 1 Setup could not verify the integrity of the file. Make sure the Cryptographic service is running on this computer
• The software has not passed Windows logo testing and will not be installed.
• Service Pack 3 installation did not complete
• An internal error occurred
• This Service Pack requires the machine to be on AC Power before setup starts.
• Service Pack 3 Setup has been canceled because Microsoft Shared Computer Toolkit for Windows XP is not compatible with this version of Windows. Before you can continue, you must: 1) Uninstall Microsoft Shared Computer Toolkit 2) (Optional) Install Windows SteadyState, the newer version of Microsoft Shared Computer Toolkit. For more detailed information, go to the Shared Access page on the Microsoft Web site.
• Service Pack 3 Setup has been canceled because Windows XP SP3 cannot be installed over RDP 6.0 MUI PACK (Update for Windows XP (KB925877)). Before you can continue, you must Uninstall KB925877.
• Microsoft Windows XP Professional Service Pack 3 cannot be applied to Windows Fundamentals for Legacy PCs (WinFLP). A unique SP3 update package for WinFLP will be made available at download.microsoft.com.
• Microsoft Windows XP Professional Service Pack 3 cannot be applied to Windows Embedded for Point of Service (WEPOS). A unique SP3 update package for WEPOS will be made available at download.microsoft.com.
• Setup cannot continue because one or more prerequisites required to install Service Pack 3 failed. For More details check the Log File Drive_Letter :\windows\svcpack.log.
• Setup has detected that another update is in progress. Please complete that installation or removal and try again.

If you have any tips (or issues) to share, feel free to leave them in the TalkBack section.