sudo su fails with 'Unable to change to sudoers gid :operation not permitted.' fault

Question

I have installed ubuntu and now I want to install flex. It asks for password but when I type my password, it asks me the password for root.

When I enter the password which I had specified during installation, it says, "Your authentication attempt was unsuccessful. Please try again."

Whether the password for root is locked or is it something else? The passwords I entered were correct.

I have also tried sudo su but it says, "Unable to change to sudoers gid :operation not permitted."

I have tried su also but when I enter the password it says, "Authentication failure".

Please help me out. I thought that maybe this is because the root user is locked by default. If so, how to recover from it? And if something else is the issue then what to do?

Solution 1

The command you're looking for is sudo -s. You can also accomplish the same thing with sudo bash

su and sudo su doesn't work on Ubuntu for security reasons. It fails because the root user does not have a password, and those operations are you attempting to "log in" as user root

Solution 2

Press Ctrl+Alt+F1, then log in and run the following command:

sudo chown -R user:user /home/user/.*

Where user is your user name, for example qasim:qasim.

Find further help here:

• http://ubuntuforums.org/showthread.php?t=2065472

• getting setgid:Operation not permitted error while running 'su' command - Ubuntu 12.04

Comments

[grimpitch]

In a terminal, sudo su is not working either?

[notkevin]

What command are you trying to run? Did you try running the command with sudo instead of becoming root with su then running the command?

[guntbert]

For voters: see OP's comment on 1st answer.

[psusi]

sudo su sure does work, it's just a bit silly to run sudo to run su, when you can just run sudo -s if you want a shell as root.

[usmangani]

I found the answer. the problem was with wubi.i have re installed with wubi12.04. and working fine.

[usmangani]

solution on askubuntu.com/questions/283950/mountcant-read-proc-mounts

[mniess]

@usmangani just a tip, don't use wubi. It is not supported any more and causes more problems than it solves. Just install Ubuntu the regular way for the best experience (and more speed).

[Brain2000]

Ctrl+Alt+F1 got me to a console login. I wasn't able to log into the GUI using root, and su/sudo wouldn't work from the guest login.