I recently had the experience of taking over IT duties for a non-profit organization and Linux was deployed in the environment for several “shared” computers. It is a common problem with these kinds of environments that support is done on a voluntary basis and as the organization grows, support changes hands frequently and credentials get lost. This environment was running Peppermint, which is an offshoot of the Mint Linux operating system but this should work on any Ubuntu or Linux Mint flavor (Xubuntu, Kubuntu, Ubuntu MATE, and so on). I did not have the administrator password in order to be able to patch the workstation or make any system level changes and whoever set this up was long gone, but this turned out to be quite an easy fix…
Shout out to Linux Uprising for this tutorial/”how to” on how to reset the password for a user.
If you forgot the administrator account password for your Ubuntu or Linux Mint system, don’t worry, it’s quite easy to set a new password and you don’t need any extra tools to do it.
Step 1 – Boot into the GRUB Menu
To start the process of setting a new admin password, boot (or reboot) the Ubuntu or Linux Mint machine and hold down the Shift key when it boots up.
Step 2 – Launch recovery Mode
From the GRUB menu, select Advanced options and press the Enter key:
On older Ubuntu / Linux Mint versions, you may not have the Advanced options menu entry, but directly the recovery mode option, so you can skip this step in that case (go to step 3).
Step 3 – Open a command line
In Advanced options, select the recovery mode GRUB menu entry by using the ? (down arrow) key to select the “root (Drop to root shell prompt)” option, then press Enter (you may need to press the Enter key twice):
You should now see the root prompt (something like root@username:~#).
Step 4 – Mount the filesystem
Remount the filesystem it with write permissions by typing this command:
mount -o rw,remount /
Step 5 – Reset the password
We can now reset the administrator account password. Type this command (replacing username with the username for which you want to change the password) to change the password:
You’ll be prompted to enter a new password, and then type it again to confirm it. Note that you won’t be able to see the password while typing it on the command line.
Make sure the changes are written to the filesystem and reboot by using these commands: