Emails sent to Hotmail are vanishing

The way that mail services define what is spam and what is not spam is very complex. If you were sending email from a server using SMTP, and the static IP address of the server was for only the one domain and nothing else, then you have a better chance of email delivery.

In my own emailing adventures (usually on shared servers), I've found that SMTP is a must, and that if possible relaying all email through a gmail account helps ensure delivery.

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