The first step is to enable the import menu in the GUI. Set the following in /etc/piler/config-site.php:
$config['ENABLE_IMPORT'] = 1;
For multitenant installations you may enable it selectively for certain customers when putting the above line to a per customer config file.
An administrator should go to administration / import menu. Then fill the imap entry form. The “type” can be either “imap” for unencrypted connection (port 143), or “imap-ssl” for encrypted connection (port 993).
Be sure to click on the “Test connection” button to verify that the GUI is able to connect with the given parameters.