# 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](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/](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 <span class="caps">UCLA</span> 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&amp;displaylang=en](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 “<span>ProgramFiles</span>\\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 <span>SystemDrive</span> /grant=administrators=f /grant=system=f  
    subinacl /subdirectories <span>windir</span>\\**.** /grant=administrators=f /grant=system=f  
    secedit /configure /cfg <span>windir</span>\\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 <span class="caps">NOT</span> install successfully for you*** , please attempt Method 3’s last 5 steps (out of 6) in **safe mode**.