Usually this happens if you terminated a cpanel account and trying to restore it from backup but somehow the MySQL user was not deleted properly.
You get this error:
[wpfmb type=’error’ theme=2]Account Creation Status: failed (Sorry, a MySQL user with the name test356 already exists.)Account Restore Failed.[/wpfmb]
Solution : Try deleting the mentioned user.
mysql mysql > use mysql; mysql > drop user test356@localhost;
OR
You can also check this using :
mysql> delete from mysql.user where user=’test356′;
Now try restoring/recreating account and see if you still receive the error.
If yes then do:
grep test356 /var/cpanel/databases/users.db grep test356 /etc/dbowners
If the user exist in the above files, delete and try again.
It will fix the error.
[wpfmb type=’info’ theme=2]if you have recently migrated your server and getting the 0MB size for all database you can check my solution here.[/wpfmb]