I got mysteriously locked out of my ubuntu 10.04 but got it solved on question http://superuser.com/questions/175175/how-to-fix-a-broken-login-in-ubuntu-10-04
Yet a big annoyance remains, if lock my screen and return, the authentication window there still won't accept my password (even though I can ctrl+alt+F1 and login in the console). I have deactivated all auto-locking configuration but that's not a long term solution for me, I though that by tinkering with /etc/pam.d/common-auth I would be able to solve the last problem but I have been unable.
Below is my current common-auth file, is there anything wrong with it? I though this was Ubuntu's default.
# # /etc/pam.d/common-auth - authentication settings common to all services # # This file is included from other service-specific PAM config files, # and should contain a list of the authentication modules that define # the central authentication scheme for use on the system # (e.g., /etc/shadow, LDAP, Kerberos, etc.). The default is to use the # traditional Unix authentication mechanisms. # # As of pam 1.0.1-6, this file is managed by pam-auth-update by default. # To take advantage of this, it is recommended that you configure any # local modules either before or after the default block, and use # pam-auth-update to manage selection of other modules. See # pam-auth-update(8) for details. # here are the per-package modules (the "Primary" block) auth required pam_shells.so auth required pam_nologin.so auth [success=2 new_authtok_reqd=2 ignore=ignore default=bad] pam_unix.so likeauth nullok_secure try_first_pass auth [success=1 default=ignore] pam_unix.so nullok_secure try_first_pass # here's the fallback if no module succeeds auth requisite pam_deny.so # prime the stack with a positive return value if there isn't one already; # this avoids us returning an error just because nothing sets a success code # since the modules above will each just jump around auth required pam_permit.so # and here are more per-package modules (the "Additional" block) auth optional pam_ecryptfs.so unwrap # end of pam-auth-update config