Microsoft 365 Delisting Service

Andrian Visnevschi andrian at
Tue Dec 6 10:09:07 UTC 2022

Dear community,

Is there anyone from the Microsoft 365 team here ? or is there anybody who
has contacts of any representative who can help with IP delisting ?

We are a cybersecurity company, protecting organizations from our own
cloud. Our IP ranges always had a good reputation and all online public
services show our IPs as good, and not listed on any spam lists / black

We have a customer who is using IP. We checked it into all
public services for IP reputation and everywhere it shows up as GOOD.
Anyway using Microsoft 365 Services, all emails are rejected:
"*Unfortunately, messages from [] weren't sent.*
*Please contact your Internet service provider since part of their network
is on our block list (S3150).*"

We tried to delist the IP many times through
<>* but it never worked... All the time we submit
the request, it says that it requires escalation, we ask for escalation and
nothing happens, we are not getting any feedback for weeks...

At the outlook ipStatus(*
) I don't see any of our IPs having an abnormal status...

Has anybody encountered the same issue ? How did you get it resolved ? It
looks very hard to cooperate with Microsoft, they keep ignoring us while
customer is complaining and the IP was never part of any spam lists/black


*Best Regards,*

Andrian Visnevschi
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