This is under version 10.4.11 on a G4 PowerBook.
The user's main account on the machine will appear to load OK, but no applications will actually launch, instead only giving the spinning beachball.
Another account on the system can be used to log in without any trouble at all.
Not being someone who normally works on Macs, I'm at a loss as to how I can diagnose or repair the problem.
Where to begin?
I did find some information on enabling the root account and I was going to use that to tar the contents of the user dir and attempt to populate a fresh user account with those materials, but the HD isn't large enough for that. I could transfer the files remotely but that will take quite a long time (the system is used for video production--there are gigs and gigs of files).
Help?
edit
Attempting to verify permissions turned up a few bad permissions, mostly on Firefox plugins for some reason, but no smoking gun. However it did stop responding at about 60%.
In system.log I found something similar to:
nfs server automount [111] not responding ns1
Might be something corrupt that it is trying to start as/for that user upon login.
You can try to run "Verify Disk Permissions", and see if that reports anything.
Also check /var/log/system.log to see if anything shows up there indicating what specific thing is the problem for that user.
edit
Based on your edits, if the verify permissions job hangs, you might have a disk issue. Try to boot into single user mode (Apple+S) during startup, and run fsck, you could also try to verify the disk inside the OS.
If that comes back clean, I would try to verify the permissions again after a fresh reboot.
Also, in the log, is the user in question the only one who has an NFS mount set up? Can you try to remove that from the users startup?
Often if a given user can not log in, it is because some of their preferences are bad.
They will have a folder called ~/Library/Preferences. If you rename the folder, and then they are able to log in, you know one of the preference files was bad. [If they can't, then it isn't a bad preference file that is causing them grief, and you'll want to restore the folder.]
If they are happy resetting their preferences, you are done. Tracking down which preference file is bad is usually not worth the effort. You could try Preferential Treatment, but, on the whole, you need to try out different files and see which ones prevent the login from occuring.
Occassionally looking at the system logs will give you some idea of what is going on. In the /Applications/Utilities folder is "Console" which helps you look at the logs. system.log is probably the most useful one to look at.