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Self-hosted e-mail service

E-mail is a time-tested protocol that needs no introduction. A personal mail server will provide special privacy for all correspondence and is useful for registering in online services and personal correspondence, especially for Delta.Chat.


Users from the “users” tab of your app are used.

Connection configuration

Login must the username with the domain. For example, user@domain.tld.


SMTP Server: your domain

SMTP Port: 587

Authentication: STARTLS

Username: your username @ your domain (your full email address)


IMAP Server: your domain

IMAP Port: 143

Authentication: STARTLS

Username: your username @ your domain (your full email address)

Configuration example for Mozilla Thunderbird

What do we use as our email server?

On the deployed server, the following components are responsible for sending, receiving, filtering emails:

  • Postfix — SMTP server;
  • Dovecot 2 — IMAP server;
  • Rspamd — SPAM filter;


Alias for addresses

Use aliases for questionable services or one-time needs.

Messages for user+alias@domain.com will go to user@domain.com. It can be useful for spam origin analysis if a unique alias is used for each online service when registering. For example, bank+user@domain.com, cryptoexchenge+user@domain.com, and so on.

Directory Filter

Create directories of filters for different purposes. This will help protect against phishing and clogging your inbox. The message for user-dir@domain.com will create a dir directory in the user@domain.com mailbox and all mail will arrive in the dir directory.


  • user-w@domain.com - for registering with web services
  • user-shops - for web-stores
  • user-pay - payment systems
  • user-forum - forum notifications


  • Email is over 50 years old. In IT, this is a sign of maturity and reliability of the technology.
  • Email is the most popular way to get infected with viruses (after hacked software and cracks).
  • Beware of phishing (fraudulent emails), it can rob you of your savings and control over your digital life.

Sending email does not work

Sending email may be blocked by your provider.

Hetzner responds that they do indeed block the email for new accounts. After one month of server operation and the first successful payment, Hetzner asks to contact support to clarify the reasons for using email. You may mention that you plan to use email to communicate with users of your services.

With DigitalOcean, such a problem has not been observed, but if you have encountered this, try to get in touch with the hosting support.

Last modified: April 8, 2024