"verify disk permissions" and "Underlying task reported failure on exit"

Question

This is more of a "How I fixed this problem, so others can benefit" posting than a current problem.
I put my MBP to sleep yesterday, and then when I tried to come out, it just sat there. After about 15 minutes, I figured I'd just force it quit and then restart.
After hitting the power button, it came up with the gray screen and apple logo with spinning gear and basically sat there for 20 minutes. Several reboot attempts were failures; sometimes I got a blue screen with spinning gears, but basically not much else.
I tried rebooting with the install disk, holding down the C key, but it gave me nothing, tried rebooting in verbose mode, tried doing CommandOption+PR, nothing, etc. So, I tried rebooting while holding down the option key, and I could see the Disk Utility.
I ran the Disk Utility to verify the disk, and that all came back fine. So, I ran Verify Disk Permissions, and i spit out "Underlying Task Reported Failure on Exit". The phone support people suggested I try reinstall with archive.
So, I tried running install with Archiving, and that failed as soon as it verified the DVD was ok - basically it couldn't access the HD.
So, I rooted around and did the following. From the Install disk, I selected "Terminal". Then, I did:
cd /Volumes
ls -lt
There I noticed that for some odd reason, Macintosh HD was listed as the following permissions:
rwxrwx---
So, admin and group had read-write-exec access to the Mac HD, but others had nothing, which I thought odd. It seems like you should at least be able to boot the computer to the login screen, and if a user is not admin or admin group, you cannot login, but I guess that's not the way it's set up.
So, I tried:
chmod o+r Macintosh HD
Then, I reran verify disk permissions. Again, I got the same "Underlying..." error. So I tried
chmod o+x Macintish HD
I then reran verify disk permissions, and it ran fine and the suggested that the Macintosh HD volume permissions should be set to:
rwxrwxr-t
So, I had the Disk Utility repair it to the way it should be, and now it all seems fine.
This suggestion basically did not come from any Apple Support people or any forums, and it seemed like such an easy fix that I'm surprised nobody (at least nobody I've found) has had the same problem or needed the same fix.
Further, I think figured out what happened. I took my computer to my local tech support guys because I wanted to turn off sharing for this MBP. So, under Macintosh HD, somebody changed the permissions under "Everyone" from "Read Only" to "No Access".
It turns out that doing this basically creates the whole problem above by making the Macintosh HD unmountable or inaccessible.
I find it truly odd that it would be so easy to remove access to the computer for mounting purposes, but this is the only thing I can think of. The tech guy realized his error and apologized and was also surprised it was so easy to hose the computer.
Anyway, this is partially a warning to everyone as well as a possible fix for the blue screen problem, especially since it was a solution I could not find anywhere.
Maybe Apple Support will see this and for its next update at least make a warning box when people try to remove "Read Only" access for "Everyone".
Good luck.

Answer 1

If your Mac still boots and runs most applications correctly, but applying Software Update packages fails and you decide to run Disk Utility to Verify Permissions and it fails almost immediately with the "underlying task reported failure on exit" explore this posting. If you see other errors, have slow/varied disk performance, or hear nasty grinding/clicking sounds you have a much more serious problem this solution isn't for you.
Use Applications, Utility, Console and check the messages appearing there each time you try Disk Utility. If you see:
Failed to open database on '/'. Error 14, 13, Permission denied.
You may have had your permissions reset on the receipts db. Which is found in
/Library/Receipts/db/a.receiptdb
At this point you have to enter the dark world of the Terminal and use a unix shell (command line).
If you are not comfortable doing find a Unix/Linux power user.
The simple fix for me was to open Applications, Utilities, Terminal and do
sudo chmod 755 /Library/Receipts/db/a.receiptdb
This allowed Disk Utility to read the file and move on to repairing permissions.
When things generate error messages in the GUI part of Mac OS X ...always go check the messages in the logs via the Console in Utilities. These messages are 'down a level' and get you much closer to the real problem.
Note that I did follow the instructions in Apple kb TS1901
http://support.apple.com/kb/TS1901
which did not help at all. Same problem each time:
xxxx-imac:Volumes user$ diskutil verifyPermissions /
Started verify/repair permissions on disk disk0s2 Macintosh HD
$<3>Error -9972: The underlying task reported failure on exit
$<3>[ + 0%..10%..20%..30%..40%..50%..60%..70%..80%..90%..100% ]
Finished verify/repair permissions on disk disk0s2 Macintosh HD
Error detected while verifying/repairing permissions on disk0s2 Macintosh HD: The underlying task reported failure on exit (-9972)
Now I wonder what changed the permissions on the receipts database file? I am off to use find and date fields to see what changed the permissions file last (my is dated sometime in November!).
flatiswhereitsat