Disc utilities didn't fix "overlapped extent allocation files"

[Irene Friedman]

I had run fsck a few times and it failed to repair "overlapped extent
allocation files"
202329d
216082d
167120d
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Since I had read that the only way to repair those was to boot from the
CD and use Disc Utility I tried that. It found only those same errors
and after three go rounds, still found them so it clearly didn't repair
them even if said "disc has been repaired." I had it "repair
permissions" next and it seemed very busy with that. Then it said all
were repaired and I didn't try that again. (What are permissions?) I
then tried Repair disc again and the same overlaps still show.

Then I quit Disc Utilty and Installer. The screen said that I hadn't
installed a new system. I could restart from the Install CD by pressing
C as I restarted or from the exisiting OS on my computer by pressing
Option as I restarted. I pressed Option...and came to a screen with a
circular arrow like the reload arrow in Safari and a right pointing
arrow and two generic pictures labeled INSTALL CD and MACHD. I tried to
choose the HD but don't think it registered. Nothing happened if I
clicked the arrows either.

Then it restarted from the darned CD!

So I restarted again pressing Option and also pressed shift f12 to eject
the CD. Then I had the screen with the 2 arrows and only the HD generic
picture. Then it restarted from my HD and all my stuff was there.

I an not impressed by Disc Utilities.

What do those overlaps mean? What can I do about them?

[Tom Stiller]

Post by Irene Friedman
I had run fsck a few times and it failed to repair "overlapped extent
allocation files"
202329d
216082d
167120d
24598d
Since I had read that the only way to repair those was to boot from the
CD and use Disc Utility I tried that. It found only those same errors
and after three go rounds, still found them so it clearly didn't repair
them even if said "disc has been repaired." I had it "repair
permissions" next and it seemed very busy with that. Then it said all
were repaired and I didn't try that again. (What are permissions?) I
then tried Repair disc again and the same overlaps still show.

Permissions are the set of file attributes that determine which users
can access files and what operations are allowed on them. They have
nothing whatever to do with the content of the files.

Post by Irene Friedman
Then I quit Disc Utilty and Installer. The screen said that I hadn't
installed a new system. I could restart from the Install CD by pressing
C as I restarted or from the exisiting OS on my computer by pressing
Option as I restarted. I pressed Option...and came to a screen with a
circular arrow like the reload arrow in Safari and a right pointing
arrow and two generic pictures labeled INSTALL CD and MACHD. I tried to
choose the HD but don't think it registered. Nothing happened if I
clicked the arrows either.

That's a surprise. Normally only volumes that contain bootable systems
are represented by those icons. It takes some time for the search for
startup volumes to complete as indicated by the 'watch" cursor. When
the cursor reverts to an arrow, one of the icons can be selected by
clicking on it and the startup process initiated by clicking on the
right point arrow. Are you sure the search had completed?

Post by Irene Friedman
Then it restarted from the darned CD!
So I restarted again pressing Option and also pressed shift f12 to eject
the CD. Then I had the screen with the 2 arrows and only the HD generic
picture. Then it restarted from my HD and all my stuff was there.
I an not impressed by Disc Utilities.
What do those overlaps mean? What can I do about them?

It means that the files in question have been allocated the same disk
sector or sectors. There is no way to repair the affected files since,
taken in pairs, at least one of them will have incorrect data recorded
in the shared sector(s). The easiest thing to do is to copy the files,
delete the originals, and inspect the copies for damage.

[Irene Friedman]

Post by Tom Stiller
That's a surprise. Normally only volumes that contain bootable systems
are represented by those icons. It takes some time for the search for
startup volumes to complete as indicated by the 'watch" cursor. When
the cursor reverts to an arrow, one of the icons can be selected by
clicking on it and the startup process initiated by clicking on the
right point arrow. Are you sure the search had completed?

Perhaps not. The watch was there but I didn't know that it was
completing a task.

After I deleted all but one of the files related to the overlap errors,
fsck found the same nodes overlapping. So I bought Disk Warrior which
found 7 overlapped files (FSCK found fewer) and it rewrote the
directory. Then it went to remount the Hard Drive and failed. Error
2168 first time, then 2168 and 4203.

It said to repeat the process. After three times I called Alsoft (the
maker of DW) but they were on Central Time and had just closed when it
was 3 pm here. I ran DW again and the same error prevented re-mounting
my hard drive. I restarted the computer as the CD said to by clicking on
on screen button...and restarted from the darn CD, so I ran DW again as
long as it was already launched. This time it worked!!!!

I restarted again holding down the touch pad clicker...( the closest I
have to a mouse button) --still restarted from CD. So I ejected the CD
and restarted. That resulted in a flashing ? for several seconds
followed by the proper start up!!!!

I'm glad DW fixed the problem but I am not happy with how it worked.

[@localhost (Simon Slavin)]

Post by Irene Friedman
I had run fsck a few times and it failed to repair "overlapped extent
allocation files"
202329d
216082d
167120d
24598d

It can't possibly fix them. This problem happens when the
pointers for two different files indicate that both files
include the same sector on disk. Since the fixing utility
can't tell which file that bit of disk really belongs in,
it doesn't know which one to change.

It's possible to write a more helpful program, of course:
one which would tell you while files need checking, copying
or deleting, but it's not a problem that can be solved
without user-intervention.