On Fri 2020-05-08 19:35:08-0700 Joseph wrote: > We are getting this messages when sending emails from our domain. > We've submitted tickets, but haven't received a response yet. Anyone > have any insights? > > 550 5.7.1 Unfortunately, messages from [1.1.1.1] weren't sent.
> It's our own address and everything on the Microsoft site says we are > clean with no issues. 1.1.1.1 is your address? You are cloudfare's anycast dns server? $ whois 1.1.1.1 [...] inetnum: 1.1.1.0 - 1.1.1.255 netname: APNIC-LABS descr: APNIC and Cloudflare DNS Resolver project -- Robert Story <http://www.isi.edu/~rstory> USC Information Sciences Institute <http://www.isi.edu/>
