Solution 1:
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Errors in the logfile /var/log/auth.log
Sep 11 07:50:04 jameszhu unix_chkpwd[3746]: check pass; user unknown
Sep 11 07:50:07 jameszhu unix_chkpwd[3747]: check pass; user unknown
Sep 11 07:50:07 jameszhu unix_chkpwd[3747]: password check Failed for user (jzhu)
Sep 11 07:50:07 jameszhu gnome-screensaver-dialog: pam_unix(gnome-screensaver:auth): authentication failure; logname= uid=1000 euid=1000 tty=:0.0 ruser= rhost=
user=jzhu
Sep 11 07:50:09 jameszhu unix_chkpwd[3749]: check pass; user unknown
1. check /etc/pam.d/gnome-screensaver,发现没有错误
2. 网上说/sbin/unix_chkpwd的属性不对，检查了也没问题
3. 查看/etc/passwd,/etc/group,/etc/shadow,/etc/gshadow发现/etc/gshadow属性不对，改为下面的样子:
-rw-r----- 1 root shadow
813 Sep
8 14:08 /etc/gshadow
-rw-r----- 1 root shadow 1455 Sep
8 14:10 /etc/shadow
Solution 2:
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I had this same issue. It turned out that my problem was thatwas updated as root,and from then on only root could read it. It stopped me from starting any X session from my username. I had to
and it worked fine after that.
~/.Xauthority
sudo rm ./.Xauthority
Reference:
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