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i have a big problem with my Ubuntu PC.

When i try sometigng need sudo or su, nothing is working and the OS Upgrade too, when i write the root password to the su command i have a "autentication error", same in the upgrades and when i try the sudo command to install something i don't have error message and nothing happen.

I was tring to make samba work when all goes wrong.

Some help!?



  1. SSH connection refused and connection closed if i try to login from secondary PC
  2. I can't access recovery mode...
  3. With the autologin i can access the system, if i logout and try to login again return the autentication error
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No solution found. I had to reinstall/fix Ubuntu from the installation/live CD – DigitalDaigor Jul 6 '13 at 1:51

It may be an issue with pam. Can you include the contents of


As a side note, you may have more luck with this question in a forum. You are probably going to have to post a lot of information specific to your system setup to solve this.

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SUDO ------------------ #%PAM-1.0 auth required readenv=1 user_readenv=0 auth required readenv=1 envfile=/etc/default/locale user_rea$ @ include common-auth @ include common-account @ include common-session-noninteractive ------------------ SU ------------------ auth sufficient session required readenv=1 session required readenv=1 envfile=/etc/default/locale session optional nopen ------------------ – DigitalDaigor Jun 28 '13 at 2:00

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