Licensing Plan High-Availability Architecture MailPlus Web Client and Mobile App The MailPlus and MailPlus Server packages allow your business to set up a secure, reliable, and private mail server, while giving your employees a modern mail client to receive and send messages. Furthermore, MailPlus and MailPlus Server are packages that can be installed on your Synology NAS, so there’s no need to rely on third-party services. Best of all, MailPlus comes with 5 free accounts and offers a cost-effective licensing plan for you. Licensing Plan Synology MailPlus comes with 5 free email accounts and allows you to add more accounts with additional purchased licenses. We provide two kinds of license packs to suit your needs: 5 or 20 units of email accounts, both with perpetual validity . The included licenses can only be applied to one Synology NAS, and cannot be migrated to another Synology NAS once activated. In addition, email aliases are not considered as email accounts and therefore do not require any license for use. High-Availability Architecture No additional fee will be charged for the high-availability support in MailPlus, and one cluster includes 10 free mail accounts by default. To have more licensed email accounts for use, you need to apply purchased license keys from Synology. For example, if you want to enable 25 email accounts in the high- availability cluster, then 15 additional licenses are needed. MailPlus Web Client and Mobile App MailPlus web client and its mobile app (available for Android™ and iOS) do not charge fees for use, and they will be updated regularly for free with MailPlus Server.