Question How to delete a non-existent database user

[Zoo3]

I faced another problem with Plesk yesterday (it solved it) and a different problem occurred.

When I run "plesk repair installation" command, the DB fails and fails.
I had previously installed RoundCube. I have deleted it now. An error occurs that can not operate the user of the DB it was using. Of course, the database does not exist by mysql command, and the user is not displayed.

ERROR 1045 (28000): Access denied for user 'roundcube'@'localhost' (using password: YES)
 Trying to reset database user password for 'roundcube@MY-DOMAIN'... ERROR 1133 (28000) at line 1: Can't find any matching row in the user tableERROR 1133 (28000) at line 1: Can't find any matching row in the user table

WARNING!
Some problems are found during reset database user password for 'roundcube@MY-DOMAIN' - database user does not exist.(see log file: /var/log/pl$
Continue...


WARNING!
Some problems are found during fix credentials for Roundcube db(see log file: /var/log/plesk/install/plesk_17.8.11_repair.log)

ERROR 1045 (28000): Access denied for user 'roundcube'@'localhost' (using password: YES)
ERROR 1133 (28000) at line 1: Can't find any matching row in the user table
ERROR 1133 (28000) at line 1: Can't find any matching row in the user table

How can I delete these "roundcube@localhost" and "roundcube@MY-DOMAIN"?

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Plesk 17.8.11, CentOS 7.6, MariaDB 10.2.23

 

[IgorG]

Try to apply solution from this KB article RoundCube webmail is not accessible on Plesk: DATABASE ERROR: CONNECTION FAILED

 

[Zoo3]

Try to apply solution from this KB article RoundCube webmail is not accessible on Plesk: DATABASE ERROR: CONNECTION FAILED

There is no RoundCube in my Plesk( Tools & Settings > Updates & Upgrades). I independently installed from source.
But this directory(/usr/share/psa-roundcube) exists on my server.

mysql> show databases like "%roundcube%";
This result is "Empty".


Once I set up with the below command, plesk repair installation is complete.

mysql>grant select on mydb.* to roundcube@'localhost' identified by 'roundcube';
mysql>grant select on mydb.* to roundcube@'mydomain' identified by 'roundcube';

But if I delete the user and run Plesk repair installation again, it fails with the same error. In other words, I do not think that the fundamental solution has been reached.