Finder doesn't launch when a specific user logs in

There are three user accounts on a system running Yosemite 10.10.1.

1. When a specific user logs in, Finder does not start.


2. The keyboard shortcut for Force Quit (Command-Option-Escape) works, but Finder is not on the list.


3. The keyboard shortcut for restart (Command-Control-Power) also works.


4. Finder does start when either of the other two users logs in.


5. In the affected account's ~/Library/Logs folder, I noticed SystemUIServer_2015-01-14-135204_ComputerName, including the following, which may or may not be relevant:

Crashed Thread: 2 Exception Type: EXC_BAD_ACCESS (SIGSEGV) Exception Codes: KERN_INVALID_ADDRESS at 0x000000010db8cca0 VM Regions Near 0x10db8cca0: VM_ALLOCATE 000000010db65000-000000010db69000 [ 16K] r--/r-- SM=S/A --> VM_ALLOCATE 000000010db8d000-000000010dbd6000 [ 292K] r--/r-- SM=SHM

How is Finder normally invoked at login, and what is the best approach to troubleshoot more deeply? I realize that deleting and replacing the user account entirely would resolve the issue, but I would like to learn what is happening and how to resolve it directly.