Hoyar SysReturn, I suppose.

Once you activated, any changes will not be written to the computer, even though you run Windows XP's built-in System Restore.

I can't find a way to break it. I need a password unless.

I have tried to spot for the services, stop it, and make changes and it still protecting the files.
Whatever changes, will not be written after system reboot.

And you ask why not uninstalling the software. Password required.