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SMTP is a standard protocol which allows to send the email messages using the Devino.Online platform servers. You can connect CRM, CMS or any other messaging system to the SMTP integration.

When sending messages via the SMTP protocol, the Devino.Online platform will automatically exclude unsubscribed and hard bounce emails.


In order to start sending email messages using SMTP protocol, it is required to:

  1. Register in the Personal Account.
  2. Provide the account manager or technical support service with the IP address that you will use for connecting to Devino.Online.
  3. Get SMTP login and SMTP password from your account manager. This information will be needed for SMTP connection.
  4. Specify the address and 25, 587 (TLS) or 465 (SSL) ports as the SMTP server for your application.



Messages are sent in UTF-8 encoding.

When sending email messages, the following conditions must be met:

  • Use a verified domain. You can manage your domains in the Personal Account.
  • Specify the correct recipient's address.
  • Do not specify several recipient's addresses in the to field, since the sending will be made only to the first address.
  • Do not send emails larger than 500 KB.
  • Do not upload files. If you need to send a file, you can attach a link.


You must always add an unsubscribe link ([Unsubscribe]) and a link to the web version ([WebVersion]) in the message.

For example:

If you want to unsubscribe from the newsletter click <a href=\"[Unsubscribe]\">here</a>
<a href=\"[WebVersion]\">Web version</a>

Error processing

If the email message validation error has occurred, the Devino.Online platform would return a standard SMTP error code 554 Transaction failed and text description of the error.

Error text Reason
Must authenticate before sending mail Incorrect login or password.
Internal server error Server error.
Message exceeds fixed size limit The acceptable email size is exceeded.
Invalid recipient address: {recipient's address} Incorrect recipient's address.
Disallowed source address: {sender's address} Unconfirmed sender's address.