SMTP unrecognized authentication type with Office 365

installation
2

try your configuration using openssl tool first

  1. Encode your office365 user
echo -n "your email here " | openssl enc -base64
xxx_encoded_email_xxx

2.Encode your password

echo -n "your password here" | openssl enc -base64
xxx_encoded_password_xxx

3.Open a connection

openssl s_client -connect SMTP.office365.com:587 -starttls smtp -quiet -crlf

4.Test authentification

  • wait for the message 250 SMTPUTF8
  • send EHLO SMTP.office365.com
  • wait for response
    250-PR3P189CA0029.outlook.office365.com Hello [88.138.0.68]
250-SIZE 157286400
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-AUTH LOGIN XOAUTH2
250-8BITMIME
250-BINARYMIME
250-CHUNKING
250 SMTPUTF8
  • send AUTH LOGIN
  • wait for 334 VXNlcm5hbWU6
  • send your encoded user login xxx_encoded_email_xxx
  • wait for 334 UGFzc3dvcmQ6
  • send your encoded password xxx_encoded_password_xxx
  • wait for response 235 2.7.0 Authentication successful
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