安裝WinXP SP3出現拒絕訪問（Access is denied)的解決方法
1. Make a backup of your registry.
用系統還原備份你的系統。
2. Download and install subinacl.exe。從微軟網站上下載並安裝subinacl.exe到系統預設的Program files目錄下。
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):
用Notepad建立一個名為reset.cmd的檔案。拷貝以下的語句到reset.cmd。以具有管理員許可權的用戶登錄並運行reset.cmd. （請耐心等候約）
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
4. Reboot at SAFE MODE and try install SP3 again.
重啟。按F8，進入安全模式。重新安裝WinXP SP3
