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Some SMTP servers ask for authentication to prevent misuse. By default Febooti Command Line Email connects to the mail server without authentication. This is very convenient in the LAN environment, where authorization is done using the local IP address of the email client.

If your SMTP requires authentication then the AUTH command must be used. The Command Line Email app supports most of the authentication methods AUTO, LOGIN, PLAIN, NTLM and CRAM-MD5 · Enable Google App passwords for SMTP

AUTO syntax

  • febootimail -AUTH AUTO

The AUTH AUTO command enables automatic detection of an authentication method, based on the SMTP server responses. This is the recommended and most suitable method for secure connection. If the server supports the STARTTLS connection, then an encrypted session is established automatically by the AUTH AUTO command.

LOGIN & PLAIN syntax

  • febootimail -AUTH LOGIN
  • febootimail -AUTH PLAIN

Both the LOGIN and PLAIN authentication methods are used to log in using the Base64 encoded passwords. Credentials are sent over an encrypted communication channel if used together with the SSL parameter, or when the STARTTLS extension is used.

NTLM syntax

  • febootimail -AUTH NTLM

NTLM (NT LAN Manager) is an Integrated Windows Authentication method. It is not necessary to provide username and password since all the necessary credentials are provided by the Microsoft Windows single sign-on mechanism. This SSO authentication without providing a username and password works when the user or server has joined a Windows Domain.

NTLM is a recommended method for the Active Directory users and servers, and the Windows Integrated Authentication must be enabled for the SMTP Service or Microsoft Exchange Server.

When sending an email from a computer or server that is not part of a Windows Domain, and has not joined an Active Directory, a username and password of the Domain user must be provided. Username can be in either username or domain\username format.

CRAM-MD5 syntax

  • febootimail -AUTH CRAM-MD5

CRAM-MD5 stands for the challenge response authentication mechanism based on the HMAC-MD5 MAC algorithm. This method is used on some types of the extended SMTP servers without TLS (Transport Layer Security).

Usually, authentication methods must be used with the USER (or USERNAME) and PASS (or PASSWORD) parameters. Febootimail passes a username and password to the outgoing mail server. The exception is NTLM, which does not require you to provide a username and password.

USER & PASS syntax

  • febootimail -AUTH AUTO -USERNAME ****** -PASSWORD *****
  • febootimail -AUTH PLAIN -USERNAME ****** -PASSWORD ******
  • febootimail -AUTH LOGIN -USER ****** -PASS ******
  • febootimail -AUTH NTLM
  • febootimail -AUTH CRAM-MD5 -USER ***** -PASS *****
febootimail -SERVER smtp.example.org -FROM ed@example.net -TO joseph@example.com -TEXT A secure SMTP authentication! -AUTH AUTO -USERNAME ed13zy -PASSWORD ds34#sC@h12 -SSL

Related commands

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