Email gets marked as spam

I am trying to setup a contact form. I can get mails to send through SMTP connection. But they are being flagged as spam because

" Why is this message in spam? It is similar to messages that were identified as spam in the past."

Here are my settings:

Mail Engine: SMTP
Content type: HTML
Email from:
Email to:

SMTP Settings: these are as provided by my host. They work fine on other CMS sites, like joomla

SMTP Server:
SMTP port: 465
Encryption: SSL

Is there way to get this message to send with it not being marked as spam :smiley:?

Two top things to avoid are (1) including links in the email, and (2) using HTML. Easiest thing to try first is just changing from HTML to plain text.