Can not log in after upgrading to snow leopard 10.6.5???!! help!!!!!

Having had this problem and "solved" it by saving recent files and all Mail folders using my machine in target mode, then restoring a 3-week old Time Machine backup and restoring recent files and Mail folders, I thank you all for the external USB drive information.

I think it may the right explanation, with the 10.6.5 update considering that if an external USB drive is accidentally disconnected at the wrong time, it can induce the loss of user accounts.

I have at least one external LaCie Rikiki drive or an Iomega drive plugged in almost permanently, but they have extremely short USB cables which mean I perch the drive on the edge of the machine, just to the left of my trackpad. Sometimes it moves slightly and a window comes up to tell me that it was not properly ejected, when I had no intention of ejecting it - there must have been a micro-disconnection when it moved. I check the connections and all is OK.

But as I also used to fire up the machine with this drive plugged in, if it moved in that way while logging in, and disconnected, perhaps that was the cause.

Anyway I now fire up the machine with no external devices attached, just as a precaution.

If this is the right explanation, I hope Apple is watching these forums and will roll out a solution soon, but also inform us!

OK it took a while but for us.. it only happens in a very very specific case.

1. os level is 10.6.5 Have not tested if it happens with earlier vers. of 10.6.Though i know it didn't happen with 10.5

2. Only happens with USB connected drives with a "Fat32" partition

3. Macos and ExFat formated usb drives and firewire drives seem fine. Also thumb drives up to 2gb so far are fine as well.

TO replicate the issue. Use a USB hard drive formatted as Fat32 log out then pull the drive. All accounts will disappear except for "other"

The way I fixed it. was to do the following:

1. Boot from OS 10.6 install dvd or os thumb drive on macbook air
2. Do reset password for the boot drive. NOT the Firmware one!
3. reboot and lot in and select "other" login as: Username: root Password: whatever you changed it to in step 2.

4. Then for each login account look in /Users to find the user folder shortname.

5. Go into System preferences and create accounts with shortnames that match each of the users folders in /Users
This will prompt you that the user already exists do you want to use the folder. Say ok.

Repeat for all other user folders except for "SHARED"

Well i fell victim to the same problem. Left MBP on overnight to transfer large amount of iTunes media files from one portable external drive to another of larger capacity. X-fered about 95GB worth, didn't take all night was just late and didn't feel like sitting up for an extra hour or so. Everything fine in AM, did some work and ejected smaller drive. Shut down to do some work on Ethernet cables. Swapped a few Cat 5 & 5e's for some better Cat 5e's and a few Cat 6's to take better advantage of Giganet (T base-1000). Reconnected everything, all is good rebooted router, switches, iMac, & MBP.
Network, & iMac booted no problem, and MBP, both with OS X 10.6.5. MBP booted normally, log on prompt popped up normally, would not accept account password. Tried several times, and yes it was the correct PW and no, Caps was not on. Tried restart, wouldn't shut down. Forced power down, and restarted. All accounts were gone and was greeted with the now famous other! No UID or PW would work.
Tried several attempts at rebooting and booting from DVD install disk. Wouldn't even recognize boot disk, kept booting to Log on screen with other! No Command & Key combo would work.
Ejected Install DVD and Booted to Single user as suggested below**, Single user was not locked so I proceeded to root and recreated new Admin account as instructed. All worked so far. However there is no trace of the old accounts left anywhere. Attempting to boot into Install DVD and Restore to last Time Machine back-up to see if it restores all to what it was yesterday...
Booted into Install DVD and have started Time Machine Restore, In work, Stay Tuned!

** Re-post of Link: http://www.hackmac.org/hacks/how-to-create-a-new-administrator-account/

Message was edited by: Rain-Man

Snoopy Dance!

Well, I'm happy to report the the Time Machine restore was successful! All is as it was! Initial reboot after restore took a few minutes but I expected that. All accounts are back and even brought back the finder screen from last nights transfer.

I hope this helps anyone else with this issue.

Invest in a good portable drive and use Time Machine, it works!

In this thread we have at least one report of the symptom affecting users of Mac OS X 10.6.4

— so I'm not over-focused on delta or combo updates to 10.6.5.

We have a number of reports of the symptom bugging users of USB devices.

Personally, I have seen the bug three times — with one USB drive (used at two computers):

• GPT (GUID Partition Table)
• three partitions
• first partition Journaled HFS+
• second partition Journaled HFS+ and used for Time Machine
• third partition NTFS-3G
• receiving power through one USB cable alone
— not using the supplementary USB-to-power cable.

That drive is profiled at http://www.wuala.com/grahamperrin/public/2010/12/22/b

One of the two computers had NTFS-3G installed. The other used Apple's driver.

One of the two received its update to Mac OS X 10.6.5 long before the USB drive was purchased.

On both computers, there is at least one user of FileVault.

----

AFAIR the first two incidents (first a MacBook Air, then an iMac) boiled down to:

a. user logged out from the OS

b. login dialogue appeared

c. user disconnected a USB drive

d. users disappeared from the login dialogue.

----

The third incident may have been slightly different. AFAIR:

a. whilst the user was logged in to his MacBook Air, we restarted the OS

b. without waiting for the restart to complete (and assuming that a backup of the user's FileVault might occur at log out time) I left that user's desk

c. some time later at my own desk I attempted a Remote Desktop connection to the laptop

d. no response, so I returned to the user's desk

e. laptop was sleeping but no obvious/immediate awakening when I touched things

f. realised that the mains power adapter was not connected to the laptop

g. pressed the power key, half expecting a slow wake using the sleepimage

h. wake was fast (so I guess that the battery had not dropped low enough to require sleepimage)

i. users disappeared from the login dialogue.

Questions for any/all readers of this thread. On the affected computer, prior to the problem:

1. Had there been any use of a USB drive with spinning hard disk (non-flash)?

2. If so:

— did that drive rely on one USB port alone for power?

— was any partition on that drive used by Time Machine?

— was any partition on that drive formatted NTFS, NTFS-3G or FAT?

3. Were there any FileVault home directories?

4. Was Sophos Anti-Virus installed?

Question 2 expanded.

AFAIR the first two incidents
(first a MacBook Air, then an iMac) boiled down to:

a. user logged out from the OS

b. login dialogue appeared

c. user disconnected a USB drive

d. users disappeared from the login dialogue.

I recall a little more detail about the first incident, affecting the MacBook Air. The user's mobile home directory had been created, using FileVault. An initial Time Machine backup of the computer was in progress, but there had been no backup of the FileVault. The log out presumably cancelled the initial backup; and AFAIR I clicked Cancel (or keyed escape) whilst the system was 'Preparing…' for the backup of the FileVault.

Hi All!

Only to note, I have made an update combo for Snow Leopard 10.6.6 in the day it was launched (about 10 days ago if I remenber). And today after a normal restart it show all my accounts, but complain that the password was incorrect. Then I restart again and all the accounts are missing. Only other and guest are available.

I did a repair permissions with Onyx and follow the instructions of llude then after the restart everything is working again!

I didn't install everything new before the problems happened, I only have a video issue with my external monitor resolution and after the reboot the problem happened with me for the first time!

I don't know if it happens to somebody in 10.6.6 version but I decide to write this post to alert everybody that this issue was not fixed with 10.6.6.

Thanks!

Just had the same problem happen to me today and I am running 10.6.6. I've got 4 user accounts, I had my 250GB USB hard drive attached via just 1 of the 2 leads and it is formatted as FAT32. I ejected it and logged out, there was another account still logged in. Unplugged the drive and all but the logged in user account disappeared.

I followed lludes instructions, and everything is working again. Have used this drive many times before but usually connect both USB leads and unplug it before logging out.

Thank you, llude.

I manage an office of predominately Macs - 20 in all...a variety of MacBooks, MacBook Pros, Mac Minis, iMacs, a Mac Mini Server, and a Mac Pro. I've had this happen twice now in under a week on two different machines. Neither of them are ones I use, so I'm trying to track down exactly what happened.

I followed the steps to delete the .applesetupdone file via single user mode and then re-setup their accounts using the exact same account names and it worked flawlessly.

But here's the machine info:

2008 Mac Pro 8-core (3,1)
OS X 10.6.6
3 user accounts

2008 20" iMac (7,1)
OS X 10.6.5
3 user accounts

Hi,
Had the same problem, and followed your instructions, but I got stuck at step 5.

When I typed:

xar -xf dslocal-backup.xar dslocal/nodes/Default/users/username.plist

the return was:

Error while extracting archive: (dslocal/nodes/Default/users): perm: could not chown file (Read-only file system) - ignored
Error while extracting archive: (dslocal/nodes/Default/users): perm: could not chmod file (Read-only file system) - ignored
Error while extracting archive: (dslocal/nodes/Default/users/username.plist): io : Could not create file (No such file or directory) - ignored

Of course I replaced username with the relevant account short name.

Any idea of what I could do to bypass / overcome this?

Thanks in advance for your help!

v.

Graham Perrin wrote:
Questions for any/all readers of this thread. On the affected computer, prior to the problem:
1. Had there been any use of a USB drive with spinning hard disk (non-flash)?

YES!

2. If so:
— did that drive rely on one USB port alone for power?

YES!

— was any partition on that drive used by Time Machine?

NO

— was any partition on that drive formatted NTFS, NTFS-3G or FAT?

YES! (FAT32)

3. Were there any FileVault home directories?

YES!

4. Was Sophos Anti-Virus installed?

NO

Graham, I don't why you asked this, but it seems to me you understood pretty much the problem

And 100000 thanks to llude: you saved my life
This nightmare happened to me just before a meeting, while doing a backup "to be safe".
The backup was OK, but I could no longer log into my computer to read it

vrevol wrote:
Hi,
Had the same problem, and followed your instructions, but I got stuck at step 5.

When I typed:

xar -xf dslocal-backup.xar dslocal/nodes/Default/users/username.plist

the return was:

Error while extracting archive: (dslocal/nodes/Default/users): perm: could not chown file (Read-only file system) - ignored
Error while extracting archive: (dslocal/nodes/Default/users): perm: could not chmod file (Read-only file system) - ignored
Error while extracting archive: (dslocal/nodes/Default/users/username.plist): io : Could not create file (No such file or directory) - ignored

Of course I replaced username with the relevant account short name.

Any idea of what I could do to bypass / overcome this?

Thanks in advance for your help!

v.

I'm having this same issue. Did you get it resolved?

If you get this error you most likely didn't mount the filesystem as read/write in step 2 of llude's instruction? This line:

/sbin/mount -uw /

(don't forget that last slash at the end)

BTW my GF ran into this issue on her Macbook Air and the local repair center didn't have a clue - this took care of it though.

Hi,

am a photographer using a iMac 27" for 1/2 year now (besides a MBP) and I had the problem too... Worked late last night, and today it would not recognize my user and password...

a disaster.

1) I would like to add, that I used two removable devices last night, which was a Sandisk 8 GB CF Card in a firewire reader, and a Kingston SD Card with the iMacs SD Card slot (had to work on some images).

2) I did the 10.6.5 upgrade a while ago and everyting seemed fine. Last update was a RAW update 2 days ago...

I used this hack to avoid reinstallation

http://www.hackmac.org/hacks/how-to-create-a-new-administrator-account/

however, while it saved the former user account I used, it did not save any program settings.. so I am currently restoring iTunes, pList settings etc.

This is serious bug, hope apple fixes it soon. I am in the iPhone developer program and will immediately report this bug from OSX, reffering to this thread.

Good luck to all,
Cheers