I posted this over at the Apple Support forums, but no luck yet, hoping someone here might have some insight: Details: 1.9 GHz G5 iMac - Tiger 10.4.11 What I've tried so far: 1. Booting into safe mode (didn't work) 2. Logging in using Fast User Switching. (didn't work) 3. Tried reinstalling the 10.4.11 combo update (had no affect) 4. Logged in as root and tried trashing preferences of corrupted user account (still couldn't login as that user!) Again, any help or advice is greatly appreciated.