I have upgraded Ubuntu to 12.04 and now I have a problem in logging in after locking the screen: it says the password is incorrect even though I provide the valid password. I found a temporary solution by switching users and logging in again with the same user.
Ubuntu – Lock screen – password incorrect
lock-screenloginpasswordupgrade
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Best Answer
I had the same issue. It is likely the ownership is wrong for
/etc/shadow
(See section "gnome-screensaver authentication failure with incorrect/etc/shadow permissions
" of this page).You need to
sudo chown root:shadow /etc/shadow
thensudo chmod u=r,g=r /etc/shadow
See this bug report.The interesting question is "Why ownership changed?". Because I don't remember changing it.