I have tryed to change the password with the information that jorge castro has put up. when i get to the UNIX password change it says (Authentication token manipulation error) then says password unchanged. is there another way to change it.
Based on the error you have posted, it sounds like you are attempting to change a user password from the root shell of the recovery console, and have missed the step of remounting the filesystem in read-write mode i.e.
mount -o remount,rw /
It would be easier to answer your question definitively if you had posted the actual steps you have taken - rather then just "with the information that jorge castro has put up".