2013-01-18 10:33:04 cwd=/home/USER/public_html/clients 3 args: /usr/sbin/sendmail -t -i
2013-01-18 10:33:04 1TwDwG-00023y-Ks <= USER@host.mydomain.com U=USER P=local S=3993 id=3e7cefe5079a84f36d64c08f99900d95@mydomain.com T="[Ticket ID: 787676] test" for EMAILUSER@hotmail.com
2013-01-18 10:33:04 cwd=/var/spool/exim 3 args: /usr/sbin/exim -Mc 1TwDwG-00023y-Ks
2013-01-18 10:33:04 1TwDwG-00023y-Ks SMTP connection outbound 1358523184 1TwDwG-00023y-Ks mydomain.com EMAILUSER@hotmail.com
2013-01-18 10:33:05 1TwDwG-00023y-Ks ** EMAILUSER@hotmail.com R=lookuphost T=remote_smtp: SMTP error from remote mail server after MAIL FROM:<USER@nhost.mydomain.com> SIZE=5115: host mx2.hotmail.com [65.55.37.72]: 550 SC-001 (COL0-MC1-F11) Unfortunately, messages from weren't sent. Please contact your Internet service provider since part of their network is on our block list. You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors.
What is wrong with hotmail? IP is not in any blacklists but hotmail won't send my emails...
I have SPF enabled in my domain.
How do I enable DKIM?