Plesk webmail + DB Error: connect failed

You may receive the following error message while accessing Webmail on a Plesk server:

A fatal error has occurred
DB Error: connect failed

You need to make sure the ‘horde’ user is able to connect to the ‘horde’ databaseusing the password mentioned in the file “/etc/psa/.webmail.shadow”. You have to create the file and specify a random password if the file is missing.
To set the password for user ‘horde’ , go to the mysql prompt.

#mysql -uadmin -p`cat /etc/psa/.psa.shadow` mysql

On the mysql prompt, execute:

mysql> update user set password=password(password-from-.webmail.shadow) where user=’horde’;

Also make sure sql.safe_mode is set to off in /etc/php.ini file:

sql.safe_mode=Off

Restart Apache server once you save the file.
If the problem persists, use the password from “/etc/psa/webmail/horde/.horde.shadow” file. Go through the following steps:

#cp /etc/psa/webmail/horde/.horde.shadow /etc/psa/.webmail.shadow

#mysql -uadmin -p`cat /etc/psa/.psa.shadow` mysql
mysql> update user set password=password(password-from-/etc/psa/webmail/horde/.horde.shadow) where user=’horde’;

You should now be able to access Webmail client.