If you send an email to yourself, when you open it in your inbox you might see an alert (like the one above) telling you the email is suspicious, and might be spoofed. Do not worry, your other recipients will not see this message!
The alert occurs only when you send something to yourself from your own email address, but routed through a different service (like IntellaSphere). The alert is triggered since your email service suspects this is a spoofing attack —which is a way for hackers to spread malware by sending out emails from an address that isn’t their own (and thereby look legitimate)—and since your Gmail or Outlook is getting an email claiming to be from your own address but which they don’t know you sent, they get jealous and assume the worst.
So, because your email provider has no way of knowing you sent the message, it is flagged as a possible threat. For your subscribers, the email will come in like any other originating from your email address. So feel free to ignore this alert and email away!