Synology Sub-Adressing/Tagging for MailStation/MailServer

… using a custom Postfix main.cf config file

1. Create custom Postfix config file: /var/packages/MailServer/etc/customize/postfix/main.cf
2. Add config value recipient_delimiter=“+” to the file
3. Stop MailServer and MailStation

   /usr/syno/bin/synopkg stop MailServer
   /usr/syno/bin/synopkg stop MailStation

4. Start MailServer and MailStation

   /usr/syno/bin/synopkg start MailServer
   /usr/syno/bin/synopkg start MailStation

5. Send a test email to your server e.g. name+YOUR_SPECIAL_VALUE@your-domain.com

The basic idea behind this is from https://blog.kastner.wtf/anleitung-recipient-delimiter-im-mailplus-server-von-synology-aktivieren/