title: SPF pass on Google and fail on Outlook
body: <p>My website has problem to send email. They go on trash on Outlook, but not on Gmail. </p>
  
  <p>I configured my DNS with this : DOMAINNAME. IN TXT "v=spf1 mx a ip4:IP -all"</p>
  
  <p>where DOMAINNAME is my domain name, IP is the server's ip.</p>
  
  <p>This is what I get from emails :</p>
  
  <ul>
  <li>Received-SPF: pass (google.com: domain of commerciale@DOMAINNAME designates IP as permitted sender)</li>
  <li>Received-SPF: fail (protection.outlook.com: domain of DOMAINNAME does not designates IP as permitted sender)</li>
  </ul>
  
  <p>I've 2 questions :</p>
  
  <ul>
  <li>Why does it work on Google and not on Outlook ?</li>
  <li>Why Google pass the domain : commerciale@DOMAINNAME and Outlook the domain DOMAINNAME (without commerciale) ?</li>
  </ul>