if you want to log on into other users computers just follow this trick….
1) start computer
2) when it asks for password press ctrl+alt+delete keys twice
3) now another window opens asking for password.
4) in this at the place of user name just type administrator….leave the password field blank and hit enter
5)wow u have logged in as a normal user
6) now u have full authority the only problem is that u can’t open my documents of the original account
6) don’t worry about this just use any file recovery software and move the files from My documents to any other folder.