When setting up the Outlook for POP and IMAP account, the function Test Account Settings failed from sending a test email message.
The following error is shown on the Tasks and Errors tabs:
Task: Sent test email message.
Error: Send test email message: The server responded: 550 5.7.1 Authentication.
This article provides a solution based on the root cause of this issue.
Root Cause Analysis
The server requires additional SMTP auth command. Users must authenticate to send messages from a local domain.
- From your Outlook POP3 and IMAP setup, go to More Settings.
- Click the Outgoing Server tab.
- Place a checkmark on My outgoing server (SMTP) requires authentication to enable it and mark Use same settings as my incoming mail server.
- Click OK to apply the changes.
Click Test Account Settings.
Tasks are now verified and completed.
NOTE: You should now be able to continue with your Outlook setup via POP3 and IMAP.