hiiiiii,,,
i put my external volume in my macbook and make in macintosh HD get info then sharing and permission and add the ownership selected me and make apply to enclosed item ,, my external volume locked and cant unlock the drive ,,,,

plzz help to unlock without format
and sorry for bad language

Did you try to reboot?

First, restart the computer and attach external drive, then open the Terminal type:
change extdrivename to your external drive name. Example:

sudo chmod -R 755 /Volumes/Calipso/

/Volumes/Calipso/ - Calipso - is the name of my external drive, Volumes - is invisible folder for external drives, CD or DVD but not for boot drive

Maybe it will help you in future:

The 7 comes from 1 + 2 + 4. This means read, write and execute permission (for the owner).
The 5 comes from 1 + 4. This means execute and read permission (for the group).
The 5 comes from 1 + 4. This means execute and read permission (for everyone).


Managing file permissions on the Mac isn't that difficult once you get the hang of it. And doinging it youself if more powerful that using Disk Utiity, however you should take care as you can screw things up when using the sudo (root permission) command.

Sorry for my English