users group

Reboot and press shift or esc before Trisquel loads. Try to press it multiple times in a sequence after BIOS. If that doesn't help, press and hold shift to get access to Grub menu. It can be tricky sometimes.

It's explained here in this link. If shift (left shift) fails to work, try with esc (escape).

https://askubuntu.com/questions/16042/how-to-get-to-the-grub-menu-at-boot-time

There's a tutorial video on the subject on YT. Watch that, I'm sure you'll get the hang of it.

https://youtu.be/m3rbpR9uuHA

Every GNU/Linux system needs a boot loader (Grub is a boot loader).

Grub's there and it has a rescue option in its menu. You'll just have to remain calm and keep your cool; press esc/shift at the right time. Try multiple times in a sequence. If you fail, try again. Eventually, you'll succeed.

If you cannot get a root shell through GRUB, here is an alternative:

1. Boot a GNU/Linux Live system such the Trisquel 8 live system: https://trisquel.info/en/wiki/starting-installable-live-system
2. Open a terminal;
3. Somehow identify the root partition of the installed system (for instance using the 'lsblk' command if you have a rough idea of its size, probably around 15 GB), the partition whose filesystem is mounted at /;
4. Let us say that partition is /dev/sdaX (where X is a number); mount its filesystem at /mnt:$ sudo mount /dev/sdaX /mnt
5. Make /mnt the root of the file hierarchy:$ sudo chroot /mnt
6. You now have the equivalent of a root terminal in the installed system. To change the password of a user whose login is "artistde":# passwd artistde

If you only remember the user name (written on the graphical login screen), 'grep' it in /etc/passwd (substitute "user name" with the actual user name or part of it):
# grep 'user name' /etc/passwd
The login is before the first ":".

Did you set the password?

# passwd your_user_name

What do you mean "change back"? You can't change back in GUI (graphically). You must have set your password. If you did that in Grub recovery, then at the login screen, type your password and log in.

Refer to post #13:

https://trisquel.info/en/forum/users-group#comment-134976

--Grub menu access shift or escape at boot
--Advanced options --> recovery mode --> drop to root shell prompt
--mount -o remount,rw /
--passwd user_name
--reboot

When you select "drop to root shell prompt", you get a small command line at the bottom. That's where you have to press enter and mount the drive read/write.

You see those little thumbnails? Click on them and they pop out as larger pictures.

--Grub menu access shift or escape at boot
--Advanced options --> recovery mode --> drop to root shell prompt
--mount -o remount,rw /
--passwd user_name
--reboot

Exact command mount:

'mount -o remount,rw /' (without quotes)

Set password:

'passwd your_user_name' (without quotes & type your own user name)

It will ask for your new UNIX password, give it (won't echo = show). That's done twice.

Then type 'reboot' (without quotes).

Are you in Grub or TTY? TTY is completely different.

You leave Grub recovery by typing 'reboot' (without quotes). Press enter after every command.

The machine should reboot. Login screen should appear.

Create a new account

# adduser peter

or

$ sudo adduser peter

Note: '#' means root ($ = user)

You should see all the account names on the login screen. If you want to leave TTY1 and go to X, press ctrl+alt+F7.

If you are logged in at TTY1, log out type 'exit' (without quotes).

You don't type the hashtag.

just type 'sudo adduser peter' (without quotes) if non-root

# = root prompt
$ = user prompt

eg.

# adduser peter
$ sudo adduser peter

If you added the new user correctly, this is what you see:

myaccount@trisquel:~$ sudo adduser newuser
[sudo] password for myaccount:
Adding user `newuser' ...
Adding new group `newuser' (1002) ...
Adding new user `newuser' (1002) with group `newuser' ...
Creating home directory `/home/newuser' ...
Copying files from `/etc/skel' ...
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
Changing the user information for newuser
Enter the new value, or press ENTER for the default
Full Name []:
Room Number []:
Work Phone []:
Home Phone []:
Other []:
Is the information correct? [Y/n] y
myaccount@trisquel:~$

After this the new user 'newuser' can be selected at the login screen. It shows up.

It is almost always useless, according to GRUB's developers:

By default, the boot loader interface is accessible to anyone with physical access to the console: anyone can select and edit any menu entry, and anyone can get direct access to a GRUB shell prompt. For most systems, this is reasonable since anyone with direct physical access has a variety of other ways to gain full access, and requiring authentication at the boot loader level would only serve to make it difficult to recover broken systems.
However, in some environments, such as kiosks, it may be appropriate to lock down the boot loader to require authentication before performing certain operations.
https://www.gnu.org/software/grub/manual/grub/html_node/Authentication-and-authorisation.html#Authentication-and-authorisation

The most common "other way to gain full access" is through a live system, as I suggested above. Encrypting user data is real security. Getting a root terminal will not decrypt those data.

If you cannot boot into a root terminal, then try to get one from a live system: https://trisquel.info/forum/users-group#comment-134959