OS X (Apple)

Hi all,
I am running OSX 10.4.11 on a G4 Sawtooth with 3 internal hard drives. Recently while setting up new user accounts for family members, I foolishly assigned 'No Access' to 2 drives other than the boot drive. Naturally, they now don't appear on the desktop. I tried to fix permissions/ownership for these drives with Disk Utility, but the volumes are indicated by a document icon and the fix permissions button is grayed out. How do I re-establish ownership? I have an admin account but am quite ignorant of Netinfo or Terminal. Many thanks

You'll need to be logged in as an administrator on the machine, then:

ls -al /Volumes/

You'll see a list of volumes. Hopefully your other volumes will be listed there. Then:

sudo chmod 755 /Volumes/yourseconddrivesname
sudo chmod 755 /Volumes/yourthirddrivesname