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I have Ubuntu Gnome 13.10. In the beginning, the first user account I created was considered as my administrator account. I changed that account to Standard now and I can't make it back to administrator and whenever I make some changes in my computer, it is asking me for a administrator password which I don't have now.

marked as duplicate by muru, karel, A.B., Takkat, user364819 May 22 '15 at 20:08

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  • I am also getting the same warning when I am trying to use sudo. @muru – Aparna k das May 22 '15 at 9:54
  • Actually in your specific case, and if you do not have any specific reasons for sticking to an old unsupported release (13.10), I'd recommend an upgrade to a newer release (e.g. 14.04) which will be more of a re-install rather than a distribution upgrade anyway. Take care to not overwrite your HOME directory (do not format the partition it is on). Create another additional emergency admin user account on installing, then re-create your old user account which should automatically point to your old HOME in case you gave it the identical name (if not you could change this later too). – Takkat May 22 '15 at 10:29

You should login as root user and add grant you sudo rights (edit /etc/sudoers). If you don't know root password, so just reset it by login into single mode (add single or init=/bin/bash to kernel line at grub menu (during boot)), then you will boot to root cli and can reset root password with passwd command.

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