I found an interesting problem. I used 1433 to set up a hidden user to enable registration (run 32. EXE registry) Right-click the table SAM and select the permission to delete the Administrator account. At the call up Task Manager point (user name), cancel the online Administrator user, then, use the "create super hidden user tool" on the Internet (this tool I found that if it is not the Administrator user to log on and establish it, it can only be found in DOS, and it can be seen in the management, therefore, after multiple tests, I found this method.) create a hidden user and return to the registry after the user is created. (Note that both modifications are run 32. EXE registry) Right-click "SAM" and select "add permissions" at "click" advanced ". Search and add the Administrator user back. After completing this operation, we will unregister the current login user, use the user you just created to log on to the system. In this way, no DOS or management tools can be found.