Hi, i installed postfix on our new root. We have a new domain too. When i send E-Mails to some Customers who got their mail at web.de or gmx.de they dont receive the mail. I get this error: 550-Reject due to policy restrictions I had this problem with Outlook/Hotmail too, but after i sent a ticket to them they whitelisted our ip and now they can receive our mails (in junk folder.. but its ok for now). I setup all records like MX, 10 ourdomain.tld. 10 mail.ourdomain.tld. SPF "v=spf1 a mx ptr -all" DKIM v=DKIM1; k=rsa; t=y; s=*; p=OURPUBLICKEY I also setup reverse IP at hetzner to our domain (ipv6 too, but i disabled ipv6 on our server for postfix). Someone know what the problem is ? I tried almost everything but now im really desperate. Kind regards xavias31