There is a specific bit in the volume information header that causes a volume
to be locked (a result similar to what happens to a floppy with the locking
tab open). You can change this bit's value by using a low-level disk editor,
such as FEdit Plus, Norton Utilities, or Symantec Utilities from Symantec Corp.
IMPORTANT: Don't do this on a disk that isn't backed up. Also, if you
don't find the 8000 located at the tenth byte in that specific sector,
get higher-level help.
Once you have started up your disk editor:
1. Open the hex representation of the volume that has the problem.
2. Go to sector number 2. (This should be the third sector on the disk with
each sector having a length of 512 bytes.)
3. The sector should look something like this:
4244 9fAE F13C 9FAF 228B 8000 0010 0003
0000 063A 0000 0200 0000 0800 0004 0000
0020 0488 0855 6E74 6974 6C65 6400 0000
...and so on, where the 4244 begins at the zero byte of the sector.
4. The key location is where you see the word containing 8000. It should be
located at the tenth byte.
5. If the 8000 is at the tenth byte, change it to 0000 and write the sector
to disk.
6. You will have to restart the system to have the change take effect, since
this information is usually stored in memory and won't be updated until
you restart.
On a related note, if you are running System 7 and you are simply not able
to rename your hard disk (though writing to it does work fine), check to
make sure file sharing is turned off. Even if you do not set the sharing
permissions for a particular volume, file sharing still makes all volumes
available to the owner for remote access. To change the name of a mounted
volume, turn file sharing off with the Sharing Setup control panel, rename
the disk, then turning file sharing back on again.