My problem is similar, but just as destivating.
The macmini crashed running safari and needed a reboot. No big deal. So, I reboot. But, when I reboot the 'login' window appeared. That's not supposed to as it is set to auto-login with a predefined account.
I'm running MacMini with 10.5.2 with all the pushed updates from Apple.
This had happened once/twice before; however, when I restarted, it would work fine. But, not this time: I've tried every other combinations of reboots over the weekend and nothing worked.
When the login window appears, I can login as root but NOTHING else.
If I goto System Preferences under Accounts, I only see 'root' and 'local administrator.' Under login options, the auto-boot from account is setup correctly.
When I goto Server preferences, the accounts are all there.
If I choose log-out and then log back in under any non-root account, it would fail.
I ran diskutil and fixed a bunch of permissions: no avail.
The "Login and Key Update 1.0" (when manually downloaded from apple's website) could not be installed (probably already picked up sometimes ago).
I'm at a loss now ... I can not access all the configurations I did for those use accounts.
What are my options? Help?