IMac 2002 reluctant to come out of retirement

Question

The model I show below is actually not the one I am referring to now; I have brought the iMac 2002 that I had put away for a few months back to my desk to use. Everything was fine until it prompted me to download a new version of iTunes, which was cool. It said in order to do that I had to download a newer version of Safari, I said cool to that too.
But ever since then it won't boot up properly. After a very long time of the spinning wheel it takes me to a PC-esque black screen where it says:
Darwin/BSD (Pdo.local) (console)
login:
Of course I don't know what this is b/c I've never had to use a login.
I booted up using the CD so I could run Disk Utility.
According to verify and repair:
"Reserved fields in the catalog record have incorrect data"
"Invalid node structure"
"Invalid sibling link"
"Invalid Key Length"
"Keys Out of Order"
These are the messages that have come up, one or two at a time, as I have tried to repair. Even if it says "repaired", when you run Verify again it shows some of the same errors.
Odd huh?
Can anyone help?
thanks! eric

Answer 1

I read on another forum about some "hidden" features in DiskWarrior v3.03. I did a Google search & found the following about Scavenge Mode.
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Use DiskWarrior's Scavenge mode
By Rob Griffiths @ MacWorld
Many people, myself included, rely on DiskWarrior to fix drives that have otherwise become unusable. In my particular case, I had a bad FireWire hub (unbeknownst to me) that was causing my FireWire drives to routinely go into never-never land. DiskWarrior (; October 2003) would then come to the rescue, rebuilding the damaged directory structure and returning the drive to a usable state—almost always without any data loss. Needless to say, DiskWarrior is a key product in my Mac’s first aid kit.
DiskWarrior normally scans directories, focusing its attention only on damaged portions of the directory structure. This makes sense, for if a given portion of the directory isn’t damaged, then there’s no need to repair it. But in some cases, you might want DiskWarrior to go ahead and scan the apparently-healthy directory information as well. Just what cases, you ask?
Assume you have some other disk repair tools in your machine’s first aid kit, and you tried some of them before running DiskWarrior. It’s possible that the other tools were able to repair the directory damage, leaving no damage for DiskWarrior to find. But it’s also possible that the repaired directory structure may not find all your stuff—so you’ve now got an apparently healthy directory, but you’re confident there are some files and folders missing.
This is where DiskWarrior’s Scavenge mode comes into play. If you hold down the Option key in DiskWarrior’s window, the Rebuild button changes to read Scavenge. In Scavenge mode, DiskWarrior will look at the entire directory structure, not just those portions that are damaged. Note that the technique used in Scavenge is the same as that used in Rebuild; it’s just that all of the directory is examined. As such, you only need to use Scavenge when the disk’s directory is fine, but you suspect that there’s data missing. As explained in the DiskWarrior manual:
Therefore, you do not need to make DiskWarrior scavenge the directory except when DiskWarrior states “All file and folder data was easily located” in the DiskWarrior Report, but you suspect that files and/or folders are still missing from the replacement directory.
I personally haven’t had the chance to test the Scavenge mode yet, but I’m glad to know there’s a way to force DiskWarrior to work with the entire directory.
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Below are some Google comments about using the Scavenge Mode
(1) I am not sure of how many people out there are aware of this, but when running DiskWarrior, if you simply hold down the Option key on the keyboard, the Rebuild button will change into a Scavenge button. Scavenge is a more-thorough scan and repair than is Rebuild.
(2) The documentation (available by going to the help menu or delving into the DiskWarrior package) says this about the scavenge command: What to Do If You Used Another Utility First
If you have used another utility before DiskWarrior and now have a directory that has no errors but is missing data, you can make DiskWarrior scavenge the directory to find the lost data if the other utility did not write over it. Hold down the Option key in step 6) Click the Rebuild button. The Rebuild button will change to Scavenge and when you press Scavenge, DiskWarrior will scavenge the directory.
Note: This is the same scavenge procedure DiskWarrior uses to recover your data when it finds directory errors, but it normally skips the scavenge procedure when the directory has no major errors. Therefore, you do not need to make DiskWarrior scavenge the directory except when DiskWarrior states “All file and folder data was easily located” in the DiskWarrior Report but you suspect that files and/or folders are still missing from the replacement directory.
(3) I recently tried to help a client with a very dodgy G5. When booted from the DW CD, I got the message that the directory was too badly damaged to repair, but to contact Alsoft support for help with more options. Called them, got a message to leave my number and they would call back, which they did within a half hour (which impressed me as well, since the message said it could be several hours). I wish I had written down the details, but the tech had me do something like hold down cmd-option, and that resulted in a new menu item that generated a code. When I gave the code to the tech, he gave me back a password, and the program then generated something like a text file of the directory. I emailed that file to him, and the next day he was able to walk me through another code/password process that then allowed me to rebuild the directory. It was amazing! Don't ever again assume that things are hopeless before calling Alsoft Tech Support, or at least trying the hint above.
I will say though, that I don't believe the Scavenge command necessarily does something *more thorough* than a normal rebuild. I think it just allows you to take a chance on fixing a really bunged up directory that otherwise might not be fixable.
(4) Recently, I dealt with a 700 MHz iMac whose owner had run the wrong version of Norton Utilities four times in a row. She was trying to take care of her machine and didn’t realize she was running incompatible software. The machine would not boot, even though DiskWarrior created a new directory. I could see that the problem lay in the directory, but didn't want to erase a machine that was not backed up.
I know that there are hidden features in DiskWarrior, but not how to access them, so I called their Technical Support. The polite gentleman who returned my call was a pleasure to speak with. After I described the problem, he told me to press a key combination in DiskWarrior, and click on a particular portion of the splash screen. A dialog with a hint appeared. He checked the hint against his list and gave me a one-time password. I clicked the Scavenge option instead of Rebuild, and a Support menu appeared with just one option, Clear Corrupted Header. DiskWarrior then rebuilt and replaced the directory and my customer’s computer was in better shape than it had been in a long time. I had discovered the best hidden feature, Alsoft’s Tech Support team.
(5) I was contacted by Marc Moorash from Alsoft, who guided me through the following process. (Well - at least up to Step 10 below).
The whole process probably took an hour from start to successful finish. I was on the phone to him for about 3 minutes!
1. Connected damaged G5 to Powerbook via Firewire 400 using Target Mode.
2. Launched Disk Warrior 3.03 from CD on the Powerbook
3. Selected the drive (Unknown Disk) to be repaired
4. Held down Ctrl+Opt and clicked on the DiskWarrior shield next to "Directory"
5. A hidden screen popped up asking for a password. It gave an 8 character hint:
6. The tech support asked for the hint and then supplied me the password.
7. A new menu appeared, called "Support". In that menu there was an option: "Clear Corrupted Volume Header ", which I selected.
8. I was then asked to click "Rebuild" and to call out each Step in the process to the tech support guy.
9. It almost immediately jumped to Step 5: Locating directory data.
10. Evidently this was good...as it meant that it had bypassed the error message I was getting previously.
11. Eventually DiskWarrior finished analyzing the volume and presented me with the option to preview the rebuilt volume:
12. I clicked on the "Preview" button and DW created a locked disk in the Finder.
13. I checked the volume: everything was fine.
14. I clicked on the "Replace" button.
15. My hard drive appeared on the desktop, and in the DiskWarrior menu.
16. I am now backing up all the data that I thought I had lost.
 Cheers, Tom