unlocking a computer

[unwashed potato!]

when a computer is locked it says only so and so can unlock this computer or an admin, what i want to know is how, whats the username and password?

My family wouldn'thave changed the password for admin so it would be cool to break into my brothers pc and screendump then change the wallpaper then when he comes home be like wtf?

 

[unwashed potato!]

well i haven't changed anything on mine and that didn't work for some reason, anyone know why?

 

[unwashed potato!]

hey thanks for the replies so far, sorry i forgot to mention that we have seperate pcs, so when isaid mine i meant my pc, and his pc, both with only 1 user name and set up as administative access or whatever its called.

i've tried with capital A, not capital, just admin but none work.

Does this help

P.S that screenshot and then remove icons was what i meant but i must have worded it badly. thanks for the suggestion anyways