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I would like to know how to reset Ubuntu to default and if it resets my terminal.

I tried to put in a command to make it if I messed up my password it would tell me something sassy. I did that in the /etc/sudoers/ file, and I messed it up. I can't use any sudo command and I would like to reset my terminal, or my whole Ubuntu set up. I tried to initiate super-user with su and I put in my password correctly, as this is a private computer, and it told me su: Authentication Failure.

If you could please tell me how I could undo my mistake I would appreciate it. This is a new computer so Factory Reset would not delete anything important. I will provide anymore detail that you may request, if I know it. I am new to Ubuntu and Linux.

marked as duplicate by muru command-line Jan 28 '18 at 5:14

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There is no such thing as 'Factory Reset' for the same reason there is no 'Restore Partition': Those features are meant to preserve your Product Key (or equivalent). Product Keys track paid software. Ubuntu does not have one.

The equivalent of a 'Factory Reset' in the Ubuntu world is to simply dig out your original install media and reinstall.


If you messed up your /etc/sudoers file you should be able to boot with your live USB and copy it over.

Completely reinstalling Ubuntu should not be necessary in such a case.

When you say "sassy" I assume you mean sudo insults.


su requires root's password rather than yours, and root is unlikely to have a password on Ubuntu, so su is generally unusable by itself.

You can try pkexec in place of sudo (as in pkexec visudo) and undo your changes to /etc/sudoers.

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