Forum Discussion

Iron Contributor

Nov 24, 2016

Office 365 Exchange Online server blacklisted

At 10:20AM 24 Nov AEST I'm seeing reports that Office 365 Exchange Online server mail-me1aus01hn0228.outbound.protection.outlook.com is appearing on different blacklist sources http://mxtoolbox.com...

exchange online

office 365

PKlapwijk

MVP

Nov 24, 2016

Hi Sonia,

Maybe same issue as my customers have: https://techcommunity.microsoft.com/t5/Exchange/Exchange-Online-send-mail-through-high-risk-delivery-pool/m-p/31640#M414

I see a lot of emails are send through the high risk delivery pool and yes this pool is on some blacklists, but the regular pool is not.

I spoke to a MS engineer yesterday, the see the last days more of this issues at customers, it is already escaleted to the team who is responsible for this.

Regards,

Peter

Sonia Cuff

Iron Contributor

Nov 24, 2016

This is where being an Exchange admin gets frustrating. On our own servers, we'd investigate, remediate and apply for the listing to be removed. With Exchange Online, Microsoft will do the same ... eventually. It just takes them longer.

On the upside I never need eseutil.

So we wait.

-Sonia

PKlapwijk
MVP
Nov 25, 2016
Microsoft confirmed the issue is resolved.
I don`t see messages send through the high risk delivery pool anymore.

Regards,

Peter
- Sonia Cuff
  Iron Contributor
  Nov 26, 2016
  Mxtoolbox.com is still reporting that Exchange Online server as being blacklisted on 6 different services.
  - PKlapwijk
    MVP
    Nov 28, 2016
    Ok, but the issue was all email send to Hotmail, Gmail etc was send via the High Risk Delivery Pool and that issue was solved. Yes this pool of servers is still on the blacklist, but this is not the server pool which is used to send. Have a look at this article for more information about the server pool:
    https://technet.microsoft.com/en-GB/library/jj200746(v=exchg.150).aspx