Clear Thinking in Data, Cloud, and AI

Using SmtpClient to send email .NET core is obsolete. The current recommendation is to use the MailKit library . Here is how to use it with the office 365 SMTP servers.

var message = new MimeMessage();
message.From.Add(new MailboxAddress("{from name}", "{from email address}"));
message.To.Add(new MailboxAddress("{to name}", "{to email address}"));
message.Subject = "{subject}";

message.Body = new TextPart("plain")
{
    Text = "{body}"
};

using (var client = new SmtpClient())
{
    await client.ConnectAsync("smtp.office365.com", 587, SecureSocketOptions.StartTls);
    await client.AuthenticateAsync("{from email address}", "{from password}");
    await client.SendAsync(message);
    await client.DisconnectAsync(true);
}

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