How can I change a MySQL user's password
There is not a way to change a MySQL user's password through cPanel. You need to delete the MySQL user and then recreate it with the new password.
Deleting a MySQL user through cPanel
[1] Click on the 'MySQL Databases' icon under the 'Databases' section.
[2] Locate the MySQL user you're wanting to delete under the 'Current Users' section.
[3] Click the delete icon [File:Cpanel_delete.jpg] to the right of the MySQL user you're wanting to delete.
[4] Click the [File:Cpanel_delete_user.jpg] button.
Create a MySQL user through cPanel
[1] Click on the 'MySQL Databases' icon under the 'Databases' section. (if you're not already there)
[2] Under the 'Add New User' section, fill in the following fields:
Username [your MySQL user will always be prepended with your cPanel username]
Password [or use the [File:Cpanel_password_generator.jpg], it will fill in the 'Password' and 'Password (Again) fields]
Password (Again)
[3] Click the [File:Cpanel_create_mysqluser.jpg] button.
The last thing to do is assign the MySQL user to the appropriate database(s). Acenet does suggest to have a different MySQL user for each of your databases for security reasons.
Assign a MySQL User to a Database
[1] Click on the 'MySQL Databases' icon under the 'Databases' section. (if you're not already there)
[2] Under the 'Add User To Database' section, select your MySQL user from the 'User' drop down.
[3] Select the database you want to assign the MySQL user to from the 'Database' drop down.
[4] Click the [File:Cpanel_add.jpg] button.
[5] Select the privileges you want the MySQL user to have.
[6] Click the [File:Cpanel_make_changes.jpg] button.