When it started back up and loaded the login page, I noticed something strange, my user was missing.  I have 4 user’s registered on my computer and now only 3 of them were showing.  So I logged in as one of the other users who an admin.

Upon login, I could see that my user’s account still existed on disk:  /Users/doug  When I went to the System Preferences, I did not list my user.  I wasn’t sure what was wrong.

I began searching through the file system and found there is a file for each user in /var/db/dslocal/nodes/Default/users/  Example:

/var/db/dslocal/nodes/Default/users/doug.plist

I opened up doug.plist and found that it was a binary file.  I could read some of the text in there and saw some mention of “Kernel” and other thing that suggested a stacktrace or dump.  I opened up the plist for another user and found that it was standard XML.  

So I copied the doug.plist from my Time Machine backup and replaced it with the one on my laptop.  I rebooted and my account was restored.

I’m not exactly sure what happened, but the moral of the store is:

1. Create a Time Machine Backup
2. Have at least one other Admin user on your computer you can login to if all fails.