How to completely delete your email on roundcube
1. Log in to your webmail: www.yourdomainname.com/webmail
2. Choose roundcube an webmail application.
3. Open Inbox. Select your email(s) you need to delete. Click Delete button.
4. Open Trash. Selete your email(s) you want to delete. Click Delete button.
5. Done. Your email(s) is completely deleted from server.