Saverio Proto wrote:
Hello,
it could be that you problem is related to DMARC.
big changes are coming, big email providers like gmail,yahoo and I
guess also hotmail are implemeting DMARC. Use of Strict DMARC Policies
will make this big providers reject emails.
https://dmarc.org/2015/10/global-mailbox-providers-deploying-dmarc-to-prote…
The senders have not published any DMARC entries - also, sometimes it
works, sometimes it doesn't. I have just tried sending mails
to "postmaster(a)hotmail.com" from a couple of our servers at Hetzner,
same error message. Other messages go through fine. (28 today sofar).
/Per
--
Per Jessen, Zürich (0.2°C)
http://www.dns24.ch/ - free dynamic DNS, made in Switzerland.