In order for the roundcube to work correctly with directadmin control panel, there’s several things need to be done.
First will be to configure roundcube default folders settings,
1.) Open the roundcube config file which located at WEBMAIL_DIR/config/main.inc.php
2.) Change the line for the default folder as below:
$rcmail_config['drafts_mbox'] = ‘Drafts’;
And change to..
$rcmail_config['drafts_mbox'] = ‘INBOX.Drafts’;
3.) Do the same for spam, Sent, and Trash folder.
4.) Next, you are require to configure the folder display array, which may referring to below:
$rcmail_config['default_folders'] = array(‘INBOX’, ‘INBOX.Drafts’, ‘INBOX.Sent’, ‘INBOX.spam’, ‘INBOX.Trash’);
5.) And also make sure to enable the default folder creation referring to below line.
$rcmail_config['create_default_folders'] = true;