So I have two accounts, A and B. A is an admin account, B is my daily use account. As of this evening, I can only log in to B if I log into A first. If I then reboot, I'm locked out of B until I log into A again. (I can log out of A at that point and still get into B, as long as I don't reboot.) I ran first aid in Disk Utility and it said everything was fine ... ? I've already blown away B's keychain and created a new one.