Roundcube is a browser-based multilingual IMAP client with an application-like user interface. It has MIME support, an address book, folder manipulation, message searching and spell checking.
Download
We are going to download and extract the 0.8 release candidate of Roundcube:
cd /path/to/roundcube
wget http://kent.dl.sourceforge.net/project/roundcubemail/roundcubemail-beta/0.8-RC/roundcubemail-0.8-rc.tar.gz
tar xvfz roundcubemail-0.8-rc.tar.gz
chown www-data:www-data * -R
mv roundcubemail-0.8-rc/* roundcubemail-0.8-rc/.gitignore roundcubemail-0.8-rc/.htaccess .
rmdir roundcubemail-0.8-rc/
rm roundcubemail-0.8-rc.tar.gz
Setup
Create a nginx config file (the WordPress version works also for Roundcube) and create a new PHP-pool. In order to get Roundcube working correctly we need to disable Suhosin, so add the following lines to the pool:
; Roundcube does not work with Suhosin enabled
php_admin_value[suhosin.session.encrypt] = disabled
Installation
Now you can complete the installation using the web-based installer at http://example.com/roundcube/installer.
The configuration will be stored in the file /path/to/roundcube/config/main.inc.php.
It is possible to make some tweaks to the file in order to improve the security. You can determine exactly to which mailservers you want your users to be able to connect to.
Most flexible for the user
// The user will be presented with a 3rd textfield where
// the hostname can be specified.
$rcmail_config['default_host'] = '';
Most intuitive for the majority of the users
// Use the part after the @-sign as the host of the mailserver,
// log in using TLS. I.e. [email protected] will become ssl://mail.example.com.
$rcmail_config['default_host'] = 'ssl://mail.%s';
Most secure
// Only use the specified mailserver, users aren't allowed to
// use other (external) mailservers.
$rcmail_config['default_host'] = 'ssl://mailserver123.example.com';