User Login(s) / Account gone - BUG - thread overview - summary - solutions?

Hello everyone...

Time to open a new thread... Seems there is a serious bug going on since a while with 10.6 randomly, hit me saturday. After working late switched off my iMac and next morning all my user accounts were gone, not able to login with my account... instead I got a "other" account.

Took me a day to get that fixed. Thanks Apple!

Same problems here:

http://discussions.apple.com/thread.jspa?threadID=2750969&tstart=0

http://discussions.apple.com/thread.jspa?messageID=13050110&#13050110

http://discussions.apple.com/thread.jspa?threadID=2747165&tstart=0

http://discussions.apple.com/thread.jspa?messageID=12880505&#12880505

http://discussions.apple.com/thread.jspa?messageID=12932314&#12932314

http://discussions.apple.com/thread.jspa?messageID=12754295&#12754295

http://discussions.apple.com/thread.jspa?messageID=12802769&#12802769

http://discussions.apple.com/thread.jspa?messageID=12640182&#12640182

http://discussions.apple.com/thread.jspa?messageID=12836318&#12836318

http://discussions.apple.com/thread.jspa?messageID=12840608&#12840608

http://discussions.apple.com/thread.jspa?messageID=12726662&#12726662

This one has a interesting solution from user Illude

http://discussions.apple.com/thread.jspa?threadID=2644133&tstart=0

This one's from cNet:

http://forums.cnet.com/7723-6126_102-505918.html

There are quite some possible solutions (from threads) that seem to help, here are some of the popular ones:

SOLUTION 1:

1 - boot up using your SL disk.
2 - select 'change password'
3 - reset the root password
4 - restart the mac from the system drive
5 - log in as root
6 - open system preferences
7 - create an account with the SAME FULL NAME and ACCOUNT NAME as your 'lost' account
8 - you will be prompted that "a folder with said name already exists - would you like to use the existing folder?" - SELECT OK
9 - log out of root
10- log into your account

SOLUTION 2 for those without TM backup:

Material needed: Snow Leopard DVD

1. Boot from DVD: restart at log in menu you're stuck in. Otherwise hard restart. Press "C" while booting.
2. Change password: in my case only System Administrator (root) and guest appeared. Change the password on System administrator.
3. log in as "System Administrator" with your new password.
4. Check to see if the folder with your user name is still there under "User"
5. Go to System Preference>Account>add account: Set same account name. That will link the new user account with old username account folder. You can also adjust the login window option. For now I checked automatic log in.
6. Restart. You should be able to log in to your old account.

SOLUTION 3 with TERMINAL (from illude - thanks!):

... I had this exact problem. I installed the 10.6.5 update and when I finally rebooted several days later, all non-system users on my machine were deleted. Only "Other" showed up in the login screen. While the users were removed from the Directory Services, their data was still intact though, as their home directories in /Users were unchanged. This is of course a big relief...

After reading this thread and the pages mentioned here, I came up with the following solution. Please replace "username" with the short (Unix) name of your user account (i.e. the one without spaces).

1. Start the computer in Single-User Mode, by holding down Command+S as it boots up. You end up in a terminal as the root user.

2. As suggested on the screen, do the following to check and mount your filesystem:

/sbin/fsck -fy
/sbin/mount -uw /

3. Find out which accounts have been deleted (here I assume 'username' is one of them):

defaults read /Library/Preferences/com.apple.preferences.accounts

4. Convince yourself that the user data is still safe:

ls /Users/username

5. I noticed that the 10.6.5 update made backups of the Directory Services and shadow passwords in /private/var/db as the xar archives 'dslocal-backup.xar' and 'shadow-backup.xar', respectively. If you also have these files, you are in luck! Restore the settings for each deleted user, as well as all shadow passwords, as follows:

cd /private/var/db
xar -xf dslocal-backup.xar dslocal/nodes/Default/users/username.plist
xar -xf shadow-backup.xar

6. For good measure, remove the record of deleted users (not sure if this is necessary, but seemed like a good idea at the time):

rm /Library/Preferences/com.apple.preferences.accounts.plist

7. Restart the computer:

shutdown -r now

I restored the settings for all deleted users in Step 5, and everyone was back after the reboot. The great thing is that all settings are restored the way they were, including the password, user GUID (which should prevent Time Machine from redoing a full backup as mentioned in this thread) and the login picture (which was stored in the JPEGPhoto field in the plist file and would have been lost otherwise).

Of course, this solution might not apply to your specific problem, so please take care when you tamper with system settings via Single-User Mode.

SOLUTION 4 using a TimeMachine Backup:

If you have a backup with time machine, reinstall with original OSX DVD.

For that type "C" when booting and hold until system boots from DVD.

Go trough necessary steps, then when asked if you want to restore from a TimeMachine Backup, do so. Will take some hours depending on how big your TM backup is and what kind of interface you use (GBit Network, USB, Firewire etc).

After that your system should be restored. However you proably have to update back again to the latest OSX update you were using with that TM backup, as OSX Mail will crash if it doesn't have that exact update environment. Example: your TM backup was done with 10.6.6., mail will crash often if you restore to 10.6.5...

ATTENTION: there may be some side effects after a restore regarding external volumes, they could be locked out as your old user settings are gone...

After restore I could not access two external drives on my system,

1) a firewire 2TB Lacie drive that was "locked". I did not have the rights to access it, and CTRL+I and setting the permissions did not work. permissions were not stored. The OSX Harddisk tool also did not work because the "owner" of that drive could not be set.

Solution: A tiny app called "BatChmod" saved the day, it allowed me "unlock" the permissions of that drive, without being a Unix superfreak knowing all the tweaks.

http://www.macchampion.com/arbysoft/BatchMod/Download.html

2) I could not access my TimeCapsule TM after restore to refresh the backup. Quite interesting because my system just had restored from that drive. The TimeMachine Volume was locked with that little "lock" symbol left of the volume symbol. CTRL+I and setting permissions did not work too... Within OSX Harddisk Tool a TimeCapsule does not show up so you can't fix permissions there either...

Solution: With Airports TimeCapsule Manual Settings there is a option to delete the volume or folders on it. deleted the sparsebundle and voila the TC could be used again.

---------

If there are any other solutions that worked out for you to recover from lost logins/accounts, please post them here, and do not forget to notify apple about that bug at

http://www.apple.com/feedback/macosx.html

so that it hopefully finally get's fixed with 10.6.7... it seems to be around since 10.5..., emerged again with 10.6 SL, and now came back with 10.6.6. so that should have been quite a long time to fix it.

Thx
Chris

Message was edited by: vertrider

Message was edited by: vertrider