anyone on from,, smtp?

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 [] weren’t sent. Please contact your Internet service provider since part of their network is on our block list (S3140). You can also refer your provider to []

It’s our own address and everything on the Microsoft site says we are clean with no issues. is your address? You are cloudfare's anycast dns server?

$ whois
inetnum: -
netname: APNIC-LABS
descr: APNIC and Cloudflare DNS Resolver project

No not at all, just replaced with a random address.

So nothing from MS as of yet, best I have gotten is these two addresses to go and file complaints. It’s been 2 days with no response, MS isn’t so attentive it seems.

So at this point we are just queuing up the messages waiting for MS to allow us to send again. What a pain.

I’ve noticed that the big mail outfits don’t take complaints seriously from small volume-mailers. They seem to assume that you’re either a big mail outfit with a ton of volume to feed their algorithms or you’re spam.