Email being sent from my Homestead account is showing up as Unauthenticated email. Couldn't verify that www.yourname.com is the actual sender and not a spammer. GMAIL
It is strange because I use Outlook and webmail regularly and do not ever see this warning message when sending to gmail addresses. One thing you can try it Outlook is to go to more settings on the account, then Advanced. Set the incoming and outgoing to use TLS security. I do not know if this is the issue or not, but you can try it.