Access denied error when installing Windows XP Service Pack 3

When attempting to upgrade Windows XP systems to Service Pack 3, you get one of the following errors:

• Service Pack 3 setup error. Access is denied.
• Service Pack 3 setup error. Service Pack installation did not complete

Checking the svcpack.log file in c:\Windows will probably show a:

• DoRegistryUpdates failed

Less common errors for Service Pack 3 installation failure include system hangs during installation— both during installation, file backup, and registry modification.

If you have followed MS KB 949377 and Windows XP SP3 still does not install for you, please read the entire article.

Per Microsoft Knowledgebase article 949377:
http://support.microsoft.com/kb/949377

Follow the steps they recommend:

• Method 1: Download and then install the full Windows XP Service Pack 3 download package from the Microsoft Download Center (e.g. if you are trying from Windows update, try to download the SP3 network install and use that to install): http://support.microsoft.com/kb/322389/
• Method 2: Method 2: Restart the computer, and then close or disable any antivirus or antispyware program that may be running. For UCLA users this typically means Sophos and Spysweeper.

If Methods #1 and #2 fail, try Method 3:

• Method 3: Reset the registry and the file permissions
• Download and then install the Subinacl.exe file. To do this, visit the following Microsoft Web site: http://www.microsoft.com/downloads/details.aspx?FamilyID=e8ba3e56-d8fe-4a91-93cf-ed6985e3927b&displaylang=en
• Start Notepad.
• Copy and then paste the following text into Notepad.
  cd /d “ProgramFiles\Windows Resource Kits\Tools”
  subinacl /subkeyreg HKEY_LOCAL_MACHINE /grant=administrators=f /grant=system=f
  subinacl /subkeyreg HKEY_CURRENT_USER /grant=administrators=f /grant=system=f
  subinacl /subkeyreg HKEY_CLASSES_ROOT /grant=administrators=f /grant=system=f
  subinacl /subdirectories SystemDrive /grant=administrators=f /grant=system=f
  subinacl /subdirectories windir\. /grant=administrators=f /grant=system=f
  secedit /configure /cfg windir\repair\secsetup.inf /db secsetup.sdb /verbose
• Save this Notepad file as Reset.cmd.
• Ensure you are running as Administrator, then double-click the Reset.cmd file to run the script. This script may take a long time to run.
• Install Windows XP SP3.

If Windows XP Service Pack 3 still does NOT install successfully for you , please attempt Method 3’s last 5 steps (out of 6) in safe mode.