Setup MySQL on Ubuntu Droplet getting error ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)

sudo /etc/init.d/mysql stop

Now start up MySQL in safe mode, so you'll skip the privileges table:

sudo mysqld_safe --skip-grant-tables &

Login with root:

mysql -uroot

And assign the DB that needs to be used:

use mysql;

Now all you have to do is reset your root password of the MySQL user and restart the MySQL service:

update user set password=PASSWORD("YOURPASSWORDHERE") where User='root';

flush privileges;

quit and restart MySQL:

quit

sudo /etc/init.d/mysql stop
sudo /etc/init.d/mysql start

Now your root password should be working with the one you just set, check it with:

mysql -u root -p