Filed under: OS, Software, Troubleshooting, Snow Leopard
Bug tracker: Snow Leopard guest accounts eating files?
Update: Cnet reports that Apple is acknowledging the problem, while calling it "extremely rare."There's a few threads on Apple's Discussion Boards describing a problem that's affecting some Snow Leopard users. An issue with the Guest account feature in SL appears to be chomping down on user data with extreme prejudice. Cnet/MacFixIt first took notice of the issue back in early September, but a 2nd report & a link from 9to5Mac have raised the threat level quite a bit.
According to affected users, the guest account's logout wipe -- a standard feature intended to prevent guests from leaving files on the machine -- is inadvertently clobbering the home directories of the non-guest accounts, with catastrophic results. One user writes, "I hadn't used my Guest Account since upgrading to snow leopard, and I accidentally clicked it instead of my user account this morning, to find that when I logged into my normal account ALL my files, settings, mail etc had been reset."
Worse of all is that he's not the only one.
MacFixIt reports that it isn't an epidemic, but readers have described the same issue in the comments to their post. For now, we offer this simple advice. First, make sure your backups are current. Secondly, turn off the Guest account feature if you're not using it (simple instructions here); some suspect that the issue is triggered by having it turned on prior to the SL upgrade. If and when the culprit is identified and squashed, we'll let you know.
Thanks to everyone who sent this in.
[Via Engadget]
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Reader Comments (Page 1 of 1)
Actionable Mango said 2:40PM on 10-12-2009
Of all the bugs I've seen, this is the most unacceptable. I do use the Guest feature, so I can't just turn it off. But now I'm too scared to let anyone use it.
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Barrie said 6:03PM on 10-12-2009
Why not set up a visitors account for guests to use and disable your Guest account. In that way there's no risk.
Gerb said 10:32PM on 10-12-2009
"I do use the Guest feature, so I can't just turn it off. But now I'm too scared to let anyone use it."
This doesn't make sense. So you're going to keep the guest feature on but not let anyone use it? Unnecessary. Just turn off the guest account and when the bug is fixed, turn it back on.
Ouila.
mvn said 2:43PM on 10-12-2009
Another one to add to their poor quality releases recently, have they sacked the QA team? itunes 9 crashing , iphone os 3.1 coma mode etc, mobile me in general, time capsule hardware only lasts 18 months, safari 3.....
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Jordan said 8:26PM on 10-12-2009
We all knew they weren't perfect, they only reason Apple was ever able to claim it "just works" is because not many people used their products. Now that more are, they're just a run of the mill company.
Dirk Simons said 2:43PM on 10-12-2009
What i would like to know is what script does this cleaning operation. Can anyone point me into this direction?
tnx!
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michaelbushnell said 2:43PM on 10-12-2009
I have guest accounts turned on, but I'm using a brand new Macbook Pro that has SL pre-installed. Hopefully this is just a problem with upgrades to SL and not full clean installs on a new system.
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Klaus said 2:53PM on 10-12-2009
I experienced the same thing over a month ago (Sep. 12th) and blogged about it back then: http://techpatio.com/2009/software/os/finally-managed-screw-mac-snow-leopard-guest-account-erased-files
At that time I didn't know it was a bug in Snow Leopard so I actually wrote the post as if *I* did something to screw up my operating system - well, now I know that's not exactly the case :)
I thought about taking a fresh backup, re-enable the guest account in SL and try to login as guest to see if it works - but I don't want the hassle of restoring (even though it *is* quite simple) in case it doesn't - I don't have enough use of the guest account... but I guess Apple will solve the issue completely with an update in the future.
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gerrynjr said 3:14PM on 10-12-2009
So far, steps to reproduce for me:
1: Clean install
2: Create initial admin user using setup wizard
3. enable guest user
4. login as guest, notice that you get the shake window, look confused
5. login as your user
6. GASP all my files are gone! (All files I have are both backed up to my NAS, as well as my desktop, so data loss wasn't an issue for me)
My only guess is that the process the erases a guest user's files upon logout is running against the first admin user of the system upon a subsequent login after logging into guest. I have not been able to reproduce this under anything other than the first admin user created with the setup utility.
Initially I thought it was due to basic Unix permissions (first user on an OSX system is usually 501) but I later noticed that the guest user account has a unix ID of 201. I do know that when the guest user logs out all files owned by 201 are deleted... somehow it was applied to 501 as well.
So yeah... my main fix for now... is to create a generic "Admin" user, the create your user. It *should* be safe then to use the Guest account, and not lose any of your data. (Dont come chase me down if it still does though!)
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Alex said 3:17PM on 10-12-2009
I'm thinking of testing this out. I'm current on all my Time Machine backups, but I never use the Guest function and I'm current on my OS X updates. I wonder if I can still trigger this.
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justin said 3:27PM on 10-12-2009
That is scary. I'm on an upgrade of SL from Leopard in which I already had Guest enabled. I have not experienced this issue.
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puhsitch said 4:03PM on 10-12-2009
Okay, just trying to understand what's going on here...
I don't know a ton about UNIX, but I'm guessing that given this situation, when the guest user files are wiped clean after logging out, there is some process running with root access that does it. If, without having to enter a password, there is an actual deletion of an admin account (as opposed to just file corruption), it couldn't happen by way of anything less than a root process, right?
I really hope that there's a less dangerous method.
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Allan L. said 6:48PM on 10-12-2009
I read about this last month. Because I have visitors who occasionally use the guest acct, I disabled it and set up a new user account called "visitor". Hope this helps. If not, I'm backed up.
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dan said 6:18PM on 10-12-2009
Another me too! Exactly this happened to me. Thought I was the only one.
It happened right after SL install and has not recurred.
Fortunately due to time machine no data was lost.
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Brad Owens said 11:18AM on 10-13-2009
Just another reason why I'm not upgrading to snow leopard... http://bit.ly/1hyCt3
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Christian Lippert said 3:49PM on 10-13-2009
I knew Snow Leopard freed up memory, but not like this!
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SableFable said 6:49AM on 10-14-2009
Unfortunately it has nothing to do with upgrading from Leopard. I did a fresh install and this happened to me the other day.
I was safe - I have all my media on a Drobo, and all my work in a Dropbox folder. I cannot praise dropbox enough - seriously, go and find out about it: http://getdropbox.com
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