http://support.apple.com/kb/ts1417

After experiencing more problems again right after New Year’s, specifically the SBBOD in all three user accounts making the iMac pretty-much unusable, I finally found the source(s) of the problems, and I must confess that I do not think that SL has been the problem. I’m passing this on so that others with issues can do some sleuthing of their systems and perhaps resolve some problems on their own, or lead themselves to a resolution.

Fundamentally, AppleCare’s advice this time was the “standard” response, “Wipe the disk and reinstall the OS and your apps.” Well, that’s a last-resort/last-ditch effort for me. Here’s what I ended up doing, and what is so far now (and hopefully for a long time) a stable system:

Having gone through running Repair Disk and Repair Disk Permissions from the installation disk (not from the hard drive) — and that having no positive effect — I stumbled upon Single-User Mode, with which you boot into Unix itself and bypass OS X (reboot and hold down Command-S). Once booted, you run this command: /sbin/fsck -fy. That fixed errors in the directory/disc structure — something that neither Repair Disk nor Repair Disk Permissions fixed. Once that completed, I was at least able to reboot into SL and all three accounts were finally usable again without encountering the constant SBBOD.

I then ran Console and looked for “I/O error” and immediately found plenty of errors on my internal (boot) hard drive. This was a serious red flag. I then ran the Apple Hardware Test (AHT) from the install disc, and it failed immediately on one of my RAM sticks (2 X 2GB DDR2 667MHz). I confirmed it with Rember. Through trial and error I isolated the faulty chip and removed it from the system (I then began the RMA process with Corsair).

An important note: I ran AHT this past summer when I was having issues, as I suspected faulty RAM: it passed even extended testing. I also downloaded and ran Rember, and it passed at the time, too. So, whatever hardware issues I was having were not showing up yet in the available diagnostics.

I installed and ran TechTool Deluxe (which comes bundled with AppleCare), and encountered enough errors on the internal hard drive that I knew I had a problem.

So, off to repair under AppleCare: my hard drive was replaced and upgraded, and the repair facility installed 10.6.6 for me. I also received the replacement RAM and installed it. I then spent the better part of two days restoring my system from a combination of fresh application installs and restored files (mostly preferences, data, documents and downloads) from both TimeMachine and a mostly-complete clone (failed due to hard drive errors) made before giving up the machine for the repair; I also restored both non-administrator User Accounts from their TimeMachine backups.

So, my iMac is FINALLY running SL superbly. New RAM, new hard drive, fresh, clean OS install. Previously, my installation was migrated from my PowerBook G4 to Leopard 10.5, and upgraded to SL 10.6. Clearly, getting rid of a lot of PPC clutter has been good for the OS performance.

Bottom line: if you’re having problems, I recommend, in this order:
1. Repair Disk and Repair Disk Permissions from the install disc.
2. Check Console logs for “I/O errors,” and if you encounter any, make sure that you have a complete disk backup.
3. Run Single-User Mode and execute /sbin/fsck -fy and note whether or not it repairs any problems.
4. Run AHT and/or Rember for memory issues.

Seems my problems were most assuredly faulty-hardware related; fortunately, I caught it before the hard drive crashed for good.

Good luck!

I’m also having to sit about 6ft from the wifi router these days, with every 10.6.x update I’ve found the ability of my laptop to pick up a signal has become worse and worse. I now have to sit in the same room as the router and only a few feet away. I used to be able to get a signal all over the house with 10.5.x (using the same hardware). My iPod touch can still get a signal all over the house, so the router isn’t the issue.
The update to 10.6.5 has pretty much put the last nail in the coffin for usable wifi on my laptop. I live near a block of flats and with 10.5.x a list of about 15 wifi signals would appear. As soon as I upgraded to 10.6 it dropped to about 5 signals. With 10.5.6 I now see only my signal if I sit in the same room as the router. As soon as I go to the next room the signal disappears altogether.
Also had the grey screen of death a few times with 10.6.x – total and immediate freezing of the computer. Press the power button to reset and do not pass go…

Told the advisor that I was hopeful for a quick fix so that I could just get back to work, I didn’t want to mess around trying different things; surely Apple knows how to fix this problem.

Well, we tried a few fixes, then I got disconnected on Apple’s end and I did not get a callback, despite both advisors I spoke with taking my phone number down (in all fairness, I have a device which causes computer telemarketer’s robo-dialers to disconnect when I answer the phone, and apparently Apple’s advisors make outgoing calls via some type of automated dialer, which seems to have disconnected the agent’s phone when I picked it up; we determined later that he did try to call but “got no answer.”

Anyway, at around 1 pm I went ahead and used the sudo mdutil -E / Terminal command to clear the Spotlight cache and re-index it. Twenty minutes later it seemed to be working (kept estimating 28-38 minutes [fluctuating] but the thermometer bar was advancing). Eventually it finished and Spotlight has been functional again ever since.

I got the Terminal commands from the Apple support site, myself. No one at AppleCare suggested it to me, and I even told two agents that I had all the Terminal commands in front of me but preferred to do it (clearing the Spotlight cache and restarting it) under their supervision, since I PAID FOR APPLECARE. Well, I ended up doing it myself and it worked and that fixed it.

I did call AppleCare back and requested a Senior Advisor, to whom I complained that they’ve got to know that this is a known problem and the procedures to take to fix it. It should have been resolved on my first call by the method that I ended up employing myself.

[PLEASE TAKE NOTE: one Senior Advisor told me, "...in the interests of full disclosure," that TimeMachine will not work without Spotlight working properly. This was not good news, as two days earlier TimeMachine saved me for the 2nd time recently where I had to restore either of two user accounts because they either became unstable or would not load at all. Be forewarned: if you are using TimeMachine make sure that Spotlight is working properly; the consequences could be painful if you have a problem and it's not working right.]

IMO, as Apple is transforming into a consumer products company, their quality has suffered with their core product: Operating Systems. Lots of people have had trouble with Snow Leopard, and iOS 4.2 is now delayed because of issues with Wi-Fi — discovered on the eve of its release.

I, for one, would much prefer that they not rush out any OS updates until they absolutely know that they are stable and glitch-free — as much as is possible given the complexity of the hardware and software implementations that we’re talking about here.

Put in 10.6.5 on Monday morning via the Combo Updater, not Software Update. Everything seemed fine in all three accounts. Went out-of-town for 30 hours, spouse and kid’s accounts working fine. I got on the iMac last night in my Admin account: Safari slow, SBBOD, klunky. Closed the other two accounts, closed my open apps (Mail, Safari, iCal), rebooted. Safari: same problems with slowness, SBBOD, klunky.

This morning I moved the Safari cache to the desktop, moved Safari to the Trash, emptied it, then installed 5.0.2 from the standalone installer. Everything’s fine since…for the time being.

Since 10.6.3, I can not update OS X without having some failure within days or weeks. I’ve gone through this now with 6.3, 6.4, and 6.5.

Very frustrating.

So, we went barely one month and things got screwy again. OS X 10.6.4, same iMac, same components.

I had to work this morning, but I took a shot at it before I left. She had a bunch of apps loaded (Word, Excel, Safari, Address Book, Grab, Text Edit, and I don’t know what else), but no app windows open except Safari. I tried Crtl-Tab and Command-Option-Esc, to no avail. Then, after a few minutes the brains seemed to get straightened out, and I could tell by the fact that the Ctrl-Tab window flashed and scrolled through all of the apps and the Force Quit window popped up and flashed repeatedly, too.

Once it was stable, I closed all of the open apps and then loaded Mail; sent the one email out that she needed to go and was what started it all. Then, I logged out of the spouse’s account, closed the open apps in my daughter’s account and logged her out, and then logged out of my Admin account; rebooted but did not wait around to load an account, just put it to sleep. Went to work.

Tonight my spouse told me that she couldn’t load her account at all (the kid was up on her account just fine). She said it gave her the log-in screen but wouldn’t load. When I tried it, it gave the log-in screen and then went to the blue screen, but after several minutes would revert to the log-in screen and not load her account.

I ran Disk Utility: no help. I reinstalled 10.6.4 from the combo updater: no help. Finally, deleted her user account and restored it from the TimeMachine backup made this morning just before all the trouble began: that worked, with the fact that Mail had to update again to the “new” version bundled in 10.6.4.

All’s fine again, but I’ve now reinstalled OS X three times (including today) since July, I’ve restored two standard user accounts since July, and I can’t seem to go more than a month without some aspect of the OS screwing up.

For the record, I have Spaces turned off; Mail is set to manually check for new mail in all user accounts and all email accounts; I reboot every 1-3 days. When Snow Leopard is working, I like it, although the degree of insecurity reminds me of Windows — which is not why I switched to the Mac over 4 years ago…

I’m sorry I every “upgraded” to Snow Leopard, as Leopard is native to this iteration of the iMac (7,1); I’d go back if I could…

We’ve got 1 Admin account and two user accounts. It’s been my summer with AppleCare — sheesh. First, as I recall, my 11-year-old’s account got trashed somehow (the report while I was at work was, “The Mac just shut itself off in the middle of using it!”). Ended up deleting/restoring her account from a TimeMachine backup.

I don’t like version 1′s of anything, so I held off on Safari 5 until 5.0.1 came out, then I figured that I was “safe.” Everything seemed to be OK for a while, I guess — except for restoring my kid’s user account. When I put in 10.6.4/Safari 5.0.2, it trashed my mail, because 10.6.4 has a new version of Mail (4.3), and it had to “update” my mail before I could use it. Spent a day rebuilding my mail setup last month.

Then, I was out-of-town on business a couple of weeks ago, and got a report from home that “Safari’s giving the SBBOD a lot and Mail’s doing the same thing.” When I got back last week, within a day it ended up crashing on me completely, would not boot, just gray screen with Apple logo and spinning gear.

Went through Hell (and back). Couldn’t run Repair Disc Permissions from the SL install disc (would hang). Agreed with AppleCare to try an OS reinstall (that would be my SECOND this summer). Being a nice guy and all, I said goodbye to AppleCare while SL was reinstalling, only to have the install hang. I gave up for the rest of the day. AppleCare was all set to schedule an in-store appointment for a suspected hardware problem, but I was in no hurry to do so after having been without the machine for five days just last month for a SuperDrive replacement…

Also, I’ve switched to a Magic Mouse, and you can’t eject an optical disc WITHOUT A WIRED APPLE MOUSE. So, Target Mode for the iMac, used my trusty old PB G4 (running Tiger 10.4.11 PERFECTLY) to eject the disc from my iMac. Came back a day later and tried to reinstall SL again, this time, mysteriously, with success. Finally narrowed my problems down to precisely TWO APPLE APPS: SAFARI and MAIL. So, trash-canned Safari and reinstalled it off of a standalone install file. Safari now stable finally.

What to do about Mail? It was now the only app that I couldn’t run without getting the SBBOD in both my admin and one user account. My only recourse: rebuild my admin Mail account and my second user account, which is how I spent most of Sunday and yesterday, after reinstalling the OS for the second time this summer, this time using the downloaded Combo Updater. I DO NOT recommend ever again letting Software Update perform an OS update, not a major app update like Safari 4 to 5.

I’ve turned off Spaces for good. I’ve killed all SmartFolders in Mail. I’ve turned off “Check for New Mail Every 5 Minutes” and I’m checking for new mail manually. What a pleasure.

Yes, I’m very sorry that I “upgraded” to 10.6. Leopard worked flawlessly on my iMac (native) from the get-go, last iteration 10.5.8. I would go back to it in an instant if I could, but even with TimeMachine it’s too much aggravation, especially after as much (otherwise free) time as I’ve spent with my iMac all summer, just trying to make it do what I bought a Mac for: to “just run.” Like my old PB running 10.4.11, and my iMac before SL…