System.Net.Mail.SmtpException: 'The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required.'

I'm trying to send a email through a C# application.

Here's the code:

using (SmtpClient smtp = new SmtpClient("smtp.zoho.com", 587))

{

smtp.EnableSsl = true;

smtp.UseDefaultCredentials = false;

smtp.Credentials = new NetworkCredential("from", "password");

using (MailMessage msg = new MailMessage("from", "to"))

{

msg.Subject = message;

msg.Body = $"[{ logEvent.Timestamp}] - { logEvent.Level} - { message}\r\n{ exceptionMessage }";

smtp.Send(msg);

}

The password is the one generated in the App Passwords menu, for that user, but I keep getting that error.

And after every time I try to send an email through code, I get the following message, in the App Passwords tab:

Looks like you are about to perform a sensitive operation. Please confirm your identity to proceed further.

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