How to Fix Windows XP Registry Permissions

The Windows registry is a hidden component of the Windows operating system that controls permissions for third-party applications as well as internal Windows components. If you have accidentally modified your Windows XP registry permissions, you may not be able to install Windows updates and will receive an "access is denied" error message. However, by resetting your registry permissions, you can get rid of these errors and get your computer back in normal working order.

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Reset your registry permissions to restore functionality to your computer.

Step

Download the "SubInACL" tool from Microsoft (see Resources). Once downloaded, run the "exe" file to install it.

Step

Launch the command prompt by selecting "Run" from the "Start" menu and then typing "cmd.exe" in the text box. Press the "Enter" key and the command prompt will appear.

Step

Copy and paste "cd /d "%ProgramFiles%\Windows Resource Kits\Tools" into the command line and then press "Enter."

Step

Repeat with the following commands. Make sure you press "Enter" after each command and that you enter them individually. rnrnsubinacl /subkeyreg HKEY_LOCAL_MACHINE /grant=administrators=f /grant=system=frnsubinacl /subkeyreg HKEY_CURRENT_USER /grant=administrators=f /grant=system=frnsubinacl /subkeyreg HKEY_CLASSES_ROOT /grant=administrators=f /grant=system=frnsubinacl /subdirectories %SystemDrive%\ /grant=administrators=f /grant=system=f

Step

Close the command window and then restart the computer. Then try performing your operation again. Your newly-reset registry should not give you any further problems.