Is the Linode address space on a black list somewhere?
My Linode host is configured as a mail server with iRedMail. I am blocked sending to Microsoft accounts (i.e. Hotmail, Outlook).
For Hotmail I get the following:
Jan 27 12:47:09 mail postfix/smtp: 22C671E47D: to=<email@example.com>, relay=mx1.hotmail.com[18.104.22.168]:25], delay=0.44, delays=0.01/0.03/0.37/0.04, dsn=5.0.0, status=bounced (host mx1.hotmail.com[22.214.171.124] said: 550 SC-001 (SNT004-MC2F7) Unfortunately, messages from 126.96.36.199 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. (in reply to MAIL FROM command)),
The error they reference: 550 SC-001, states:
"Mail rejected by Outlook.com for policy reasons. Reasons for rejection may be related to content with spam-like characteristics or IP/domain reputation. If you are not an email/network admin please contact your Email/Internet Service Provider for help"
The mail is not "spam-like" so it must be the reputation of the IP/domain.
For Outlook I get:
Jan 27 12:47:51 mail postfix/smtp: D81AF1E47D: to=<firstname.lastname@example.org>, relay=schreblerlaw-com.mail.protection.outlook.com[188.8.131.52]:25], delay=6.3, delays=0.01/0/0.62/5.6, dsn=5.7.1, status=bounced (host mail.protection.outlook.com[184.108.40.206] said: 550 5.7.1 Service unavailable; Client host [220.127.116.11] blocked using FBLW15; To request removal from this list please forward this message to email@example.com (in reply to RCPT TO command))
I've requested delisting but have heard nothing back.