I run into this one quite often, a user tries logging in to their account and all that comes up is their desktop background and the little blue spotlight magnifying glass in the upper right hand corner. From there on nothing happens. You can log on using a different account, but the account in question just refuses to work. Here’s how to fix it…
To start out try doing a filesystem check and see if its able to fix the problem, in my experience most of the time it doesn’t, but it’s worth a shot.
1. Turn on the computer and hold down command(apple key) and the s key simultaneously. Go ahead and release once you start seeing all the command line stuff.
2. Type fsck -fy hit return.
3. When the check is complete type reboot and hit return.
There a chance you might be fixed now, if not follow this next set of instructions…
1. Turn the machine on and hold down the Shift key.(This will start the machine in safe mode)
2. Log on as the user in question, don’t worry it should lock up on you in safe mode.
3. Open up Terminal it is located within applications in the utilities folder.
4. Type cd /Users/username/Library/Preferences
5. Type rm com.apple.finder.plist
6. Type rm com.apple.spotlight.plist
7. Reboot you should now be up and running