I have the same symptoms. No user names > 8 characters. No non-alpha characters in user names. No non-alpha characters in passwords (yeah I know, home PC). No password >8 characters.
Still, cannot log on certain users (2), but can others (other 2). I get the error or warning
gdm-simple-greeter[32458]: WARNING: Unable to lookup user name data: Success
This might be introduced relatively recent (about 2-4 weeks) since these users rarely logged on. They are now locked out - I don't know why that can be.
I have the same symptoms. No user names > 8 characters. No non-alpha characters in user names. No non-alpha characters in passwords (yeah I know, home PC). No password >8 characters.
Still, cannot log on certain users (2), but can others (other 2). I get the error or warning
gdm-simple- greeter[ 32458]: WARNING: Unable to lookup user name data: Success
This might be introduced relatively recent (about 2-4 weeks) since these users rarely logged on. They are now locked out - I don't know why that can be.