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SQL SERVER - Database Mail Error: The SMTP Server Requires a Secure Connection or the Client was not Authenticated. The Server Response Was: 5.5.1 - SQL Authority with Pinal Dave
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Send email in VB, VBA, ASP, C++, Delphi directly without specified SMTP server - DNS lookup MX record
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Enable to send email, server reported error" or "Email server reported an error ... Could not connect to SMTP host" error when trying to send email inside 'Command Center'
![Alex Xu on Twitter: "/3 2. Outlook mail server queries the DNS (not shown in the diagram) to find the address of the recipient's SMTP server. In this case, it is Gmail's Alex Xu on Twitter: "/3 2. Outlook mail server queries the DNS (not shown in the diagram) to find the address of the recipient's SMTP server. In this case, it is Gmail's](https://pbs.twimg.com/media/Fh29OxbVsAEW4P9.jpg:large)