Lolipop by GMO cloud is the hosting service I’m using. The hosting plan includes email hosting services, but the webmail interface is in Japanese with limited functions provided, so I installed my own Roundcube instance instead. Not like VPS, Installing a custom Webmail service needs to skim through the service provider’s documentation, undoubtedly it is all in Japanese. This takes me some time to search and validate all these endpoints. Anyway, the tutorial is as follows.

Firstly, get the full Roundcube installation directory.

install the Roundcube in your hosting directory. I installed Roundcube with SQLite database. Then copy the Roundcube directory path.
For the config file, Roundcube config uses the absolute path of the server, which means your home directory prefix needs to be appended. The home directory prefix can be found here:

Or a simple PHP script can do the trick as well:

<?php
$path = new SplFileInfo(__FILE__);
echo 'The real path is ' . $path->getRealPath();

Secondly, Check the IMAP and SMTP server addresses.

IMAP and SMTP info can be found above, both IAMP and SMTP use Implicit TLS.

Finally, update the config file.

In the config directory, update the configuration file. Here is my template:

<?php

/* Local configuration for Roundcube Webmail */

// ----------------------------------
// SQL DATABASE
// ----------------------------------
// Database connection string (DSN) for read+write operations
// Format (compatible with PEAR MDB2): db_provider://user:password@host/database
// Currently supported db_providers: mysql, pgsql, sqlite, mssql, sqlsrv, oracle
// For examples see http://pear.php.net/manual/en/package.database.mdb2.intro-dsn.php
// Note: for SQLite use absolute path (Linux): 'sqlite:////full/path/to/sqlite.db?mode=0646'
//       or (Windows): 'sqlite:///C:/full/path/to/sqlite.db'
// Note: Various drivers support various additional arguments for connection,
//       for Mysql: key, cipher, cert, capath, ca, verify_server_cert,
//       for Postgres: application_name, sslmode, sslcert, sslkey, sslrootcert, sslcrl, sslcompression, service.
//       e.g. 'mysql://roundcube:@localhost/roundcubemail?verify_server_cert=false'
$config['db_dsnw'] = 'sqlite:////home/users/1/YOUR-LOLIPOP-DOMAINI/web/SUBDIR-TO-ROUNDCUBE/mail.db?mode=0646';

// ----------------------------------
// IMAP
// ----------------------------------
// The IMAP host chosen to perform the log-in.
// Leave blank to show a textbox at login, give a list of hosts
// to display a pulldown menu or set one host as string.
// Enter hostname with prefix ssl:// to use Implicit TLS, or use
// prefix tls:// to use STARTTLS.
// Supported replacement variables:
// %n - hostname ($_SERVER['SERVER_NAME'])
// %t - hostname without the first part
// %d - domain (http hostname $_SERVER['HTTP_HOST'] without the first part)
// %s - domain name after the '@' from e-mail address provided at login screen
// For example %n = mail.domain.tld, %t = domain.tld
// WARNING: After hostname change update of mail_host column in users table is
//          required to match old user data records with the new host.
$config['default_host'] = 'ssl://imap.lolipop.jp';

// TCP port used for IMAP connections
$config['default_port'] = 993;

// ----------------------------------
// SMTP
// ----------------------------------
// SMTP server host (for sending mails).
// Enter hostname with prefix ssl:// to use Implicit TLS, or use
// prefix tls:// to use STARTTLS.
// Supported replacement variables:
// %h - user's IMAP hostname
// %n - hostname ($_SERVER['SERVER_NAME'])
// %t - hostname without the first part
// %d - domain (http hostname $_SERVER['HTTP_HOST'] without the first part)
// %z - IMAP domain (IMAP hostname without the first part)
// For example %n = mail.domain.tld, %t = domain.tld
$config['smtp_server'] = 'ssl://smtp.lolipop.jp';

// SMTP port. Use 25 for cleartext, 465 for Implicit TLS, or 587 for STARTTLS (default)
$config['smtp_port'] = 465;

// provide an URL where a user can get support for this Roundcube installation
// PLEASE DO NOT LINK TO THE ROUNDCUBE.NET WEBSITE HERE!
$config['support_url'] = '';

// This key is used for encrypting purposes, like storing of imap password
// in the session. For historical reasons it's called DES_key, but it's used
// with any configured cipher_method (see below).
// For the default cipher_method a required key length is 24 characters.
$config['des_key'] = 'xTxqnP1CB5EwUPv0BEDzja9C';

// Automatically add this domain to user names for login
// Only for IMAP servers that require full e-mail addresses for login
// Specify an array with 'host' => 'domain' values to support multiple hosts
// Supported replacement variables:
// %h - user's IMAP hostname
// %n - hostname ($_SERVER['SERVER_NAME'])
// %t - hostname without the first part
// %d - domain (http hostname $_SERVER['HTTP_HOST'] without the first part)
// %z - IMAP domain (IMAP hostname without the first part)
// For example %n = mail.domain.tld, %t = domain.tld
$config['username_domain'] = 'YOURDOMAIN.HERE';

// ----------------------------------
// PLUGINS
// ----------------------------------
// List of active plugins (in plugins/ directory)
$config['plugins'] = array();

Point your browser to Roundcube’s URI and that should work.

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