RoundCube CONNECTION FAILED Database Error

Sometimes, we experience different errors while logging into an email account. One of such error message is 'Database Error: CONNECTION FAILED' in Roundcube.

This error is mainly based on the database trouble in the server. Also, it mainly shows while trying to log in to Roundcube. Any updates made in the DirectAdmin can also end up with these errors.

Here at Ibmi Media, as part of our Server Management Services, we regularly help our Customers to fix Roundcube related errors.

In this context, we shall look into the main causes and fixes to Database error in Roundcube DirectAdmin.

Causes of Database Error: CONNECTION FAILED in RoundCube and how we fix it?

Roundcube is a popularly used webmail client that is written in PHP. And all the data of Roundcube is stored in a database.

Basically, the database plays a major role in Roundcube's functionality. It is very necessary for the database to be up and running well.

Here, we will see different methods to fix the error related to RoundCube in DirectAdmin.

1. Empty database

Recently, one of our customers approached us with a Roundcube error.  He received the below error message while logging into Roundcube:

Unable to connect to the database!
Please contact your server-administrator.

Our Support Experts started to troubleshoot the error by checking the database. The database was available in the account. But there were no tables within it. So, we deleted the database using the command:

drop database database_name

Then, we ran the below command for the re-working of the RoundCube  webmail client:

./build roundcube

Finally, this fixed the error message.

2. Database doesn't exist

Sometimes, the database itself goes missing in some accounts which don’t allow the RoundCube to work.

Here is an example where our customer experienced the same error message:


We investigated this error and found that the database was not existing in the account.

Also, the database was not present in /var/lib/mysql path. So we ran the build script provided below to fix this error.

./build roundcube


3. MySQL functions missing in php.ini

RoundCube is open-source software written in PHP. There can be cases where few functions in the php.ini file will not be set by default.

So, the error will resolve if we set those PHP functions properly. One of our customers was experiencing the same error.

Our Support Experts found that pdo_mysql.default_socket was not set in the php.ini file.

We, enabled pdo_mysql.default_socket by pointing it to /tmp/mysql.sock. Then, we restarted the php-fpm and this solved the problem.

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This article will guide you on the different methods to fix Database Error: Connection Failed error shows up due to database errors or #PHP #errors. 

Establishing a Database Connection #Error basically means that for some reason or another the PHP code was unable to connect to your #MySQL database to retrieve the information it needs to fully build that page. That's why the error is always shown on a blank page because there is no information about your site as it is not connected to your database.

Establishing a Database Connection Error Occur due to:

1. Incorrect Login Credentials.

2. Corrupt #Database