mysqli_real_connect(): (HY000/1045): Access denied for user 'phpmyadmin'@'localhost' (using password: YES)

Question

I am doing an online course from coursera where they tolm me to install phpmyadmin.

NOW I am a total beginner in this thing so I am not able to do much research upon that and now somehow, after I installed MySQL and phpmyadmin, in the localhost, I am getting some errors, is that common? Because the other participants in the course are not getting them. If that's fatal or will limit some of my obvious abilities, please tell me how to cure it.

BTW If you didn't noticed the errors are:

mysqli_real_connect(): (HY000/1045): Access denied for user 'phpmyadmin'@'localhost' (using password: YES)

and

Connection for controluser as defined in your configuration failed.

Some more details:

1. PHP version is 7.4
2. Operating System is Ubuntu 20.04

Answer 1

I've just installed LAMP on a new PC, and got the same problem.
Linux Mint 20 + MariaDB.
Password for root and phpmyadmin was already ok, but the error was still there.

Finally I discovered another configuration file, that sets the phpmyadmin password; you have to edit it:

$ sudo nano /etc/dbconfig-common/phpmyadmin.conf

set the correct password (= dbc_dbpass) for user dbc_dbuser='phpmyadmin'
Use ctrl-O to save, then ctrl-X to exit. Then launch the command:

$ sudo dpkg-reconfigure phpmyadmin

(Do NOT reinstall the DB).
In my PC il works!

Answer 2

I was using MaridDb solved this issue with the following:

sudo systemctl stop mariadb
sudo mysqld_safe --skip-grant-tables --skip-networking &
mysql -u root

You will see a prompt like below:

Type help; or \h for help. Type \c to clear the current input statement.

MariaDB [(none)]> FLUSH PRIVILEGES;

For MySQL 5.7.6 and newer as well as MariaDB 10.1.20 and newer

ALTER USER 'root'@'localhost' IDENTIFIED BY 'new_password';

OR:

For MySQL 5.7.5 and older as well as MariaDB 10.1.20

SET PASSWORD FOR 'root'@'localhost' = PASSWORD('new_password');