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outlookssmtp

I am unable to send and receive mails via Outlook. I keep getting the following error message from ssmtp.

ssmtp: 550 5.3.4 554-554 5.2.0 STOREDRV.Deliver; delivery result banner

Here is the content of /etc/ssmtp/ssmtp.conf:

root=myemail@outlook.com
mailhub=smtp-mail.outlook.com:587
AuthUser=myemail@outlook.com
AuthPass=mypassword
UseSTARTTLS=YES
hostname=sierra-test
FromLineOverride=YES

Best Answer

Please extend your question with your platform details (distribution, version, ssmtp version, where did you installed from, etc.).

Regarding your config file:

/etc/ssmtp/ssmtp.conf

A few issues I see (which might or might not apply, depending on version):

  1. The hostname should have a FQDN (fully qualified domain name), else Outlook (or Gmail, Yahoo and others) might reject it. You could try adding one.
  2. You seem to be missing "AuthMethod".
  3. Some say that UseTLS and UseSTARTTLS exclude each other, others place both settings. You could try swaping between those options.

Example:

root=myemail@outlook.com
FromLineOverride=YES    # usually goes with root
mailhub=smtp-mail.outlook.com:587
rewriteDomain=outlook.com    # shouldn't be needed if you are not overwriting from, but doesn't hurt
AuthUser=myemail@outlook.com
AuthPass=mypassword
AuthMethod=LOGIN             # could be plain or cram-md5 for ex. 
UseTLS=Yes                   # this one might be yes or no
UseSTARTTLS=Yes 
hostname=sierra-test.domain.com  # full domain here, might help

You do have to keep in mind that if you enabled 2FA (two factor authentication) for you email/account, you will need to validate it before it allows you to send email.

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