Dear Users, when I opened my mac book pro today I found apart fro me (I am the administrator and no body has had in hands this laptop) there is another user with name and surname. How could that happen? I must add that the computer was protected with a password which showed immediately after switching the computer on... Is it a hacker? I deleted his account as a whole from the computer at Settings-User and Groups- and on the left there were some +- and settings sign. I also called Apple, but they couldn't give any suggestion how and who was the hacker. How to restet the MacBokPro? What can I do more to protect my laptop and prevent future guests? Many thanks!!!