XP Service Pack 3 Set-Up X Access Denied.

While YOU downloading Service Pack 3 got this message:

Service Pack 3 Set-Up X Access Denied.

The problem may be with the xp registry on your computer. I found the following fix that worked:

1. Make a backup of your registry.
2. Download and install subinacl.exe.
3. Create a file called reset.cmd with Notepad. Copy the text below into the file reset.cmd and run reset.cmd with administrative rights (it may take a LONG time):

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%\inf\defltbase.inf /db defltbase.sdb /verbose


subinacl.exe can be downloaded from microsoft.

Download details: SubInACL (SubInACL.exe)

Windows XP Service Pack 3 - ISO-9660 CD Image

Download here

Resetting the Registry and the File Permissions

Using SECEDIT.EXE in Windows XP Professional

In Windows XP Professional, you may use the following secedit command-line to reset the file and registry permissions to defaults.

secedit /configure /cfg %windir%\repair\secsetup.inf /db secsetup.sdb /verbose

For more information, see article How to reset security settings back to the defaults.