I was unable to copy my files from my external hard drive to my laptop so I changed all the priviledges to read & write and apply to everythign inside both laptop & external and now external is LOCKED. Called apple twice, no help, found some threads about terminal commands, all looked good until the last command said ACL or whatever couldn't be verified..and now brand new laptop freezes on start up. freaking out in central america-if anyone can help I can provide lots more details thanks