I wanted to delete my old time machine backup from my western digital mybook world
i didnt need it for anything, as I have a backup of it :D

i found two ways to do it.

method 1 – ssh.

if you have ssh enabled on your mybook world then you can

open terminal > ssh to your mybook

rm -rf /DataVolume/.timemachine
mkdir /DataVolume/.timemachine
chmod 777 /DataVolume/.timemachine

you have just deleted the time machine folder, and made a new one.

method 2 – finder

if you open finder you will see your mybook world in the left sidebar.
click it, then go to connect as.
type in wd_backup as the username and backup as the password (unless you changed it)
it will then connect and you will see a file.
delete it.

all done