Enabling Basic Authentication
If you host your company emails with Microsoft Office365, you need to reconfigure the SMTP and security settings in your Microsoft Portal.
There’s a known issue with dock'd utilising your email accounts that started in June/July 2022 around modern authentication. Microsoft Office365 and Azure AD both come with security defaults unless otherwise stated. Known Issue Article: https://learn.microsoft.com/en-us/answers/questions/898488/the-server-response-was-5757-client-not-authentica.html
Remediation
Step 1: Login to your Microsoft Office365 Admin Console and Check “Settings > Org Settings > modern authentication”.
Step 2: If it’s turned on, you need to head over to the Azure AD Portal then:
Click on Properties
Disable Security Defaults
Step 3: Head back to your Microsoft Office365 Admin Console and refresh the modern authentication page. If it works correctly, you should see options for Basic Authentication (i.e., SSL, SMTP Authentication etc.)
Step 4. Ensure that the SMTP Protocol is enabled for any email accounts you wish dock'd to send from
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