Authenticate without domain part in email address


Check out the lightweight on-premises email archiving software developed by iRedMail team: Spider Email Archiver.

With default settings, client must use full email address as username for POP3/IMAP/SMTP/webmail login, if you want to login without domain name part in email address, please follow below steps.


Open Dovecot config file /etc/dovecot/dovecot.conf (Linux/OpenBSD) or /usr/local/etc/dovecot/dovecot.conf (FreeBSD), find parameter auth_default_realm, set the domain name you want to allow user to login without domain name part in email address. For example:

auth_default_realm =

Restarting Dovecot is required. After restarted Dovecot, user logins as john.smith will be rewritten to by Dovecot. This works for POP3/IMAP/SMTP services.

Roundcube Webmail

Open Roundcube webmail config file config/, find parameter $config['username_domain'], list your domain name in this parameter. For example:

// 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'] = '';

Restarting web server (Apache or php-fpm) is recommended.