Michael, this seems related to a Microsoft known issue: https://learn.microsoft.com/en-us/answers/questions/1388775/outlook-com-servers-tells-server-busy-please-try-a Regards Giovanni
Il 11 ottobre 2023 20:07:13 CEST, Michael Wise via mailop <[email protected]> ha scritto: > >That's volume throttling, not IP blocking. >Did you recently bring a new block online, or ... someone sending out an >abnormally large volume of mail? >If it's going out thru shared IPs, that could also be part of the problem, but >this is just speculation. > >Aloha, >Michael. >-- >Michael J Wise >Microsoft Corporation| Spam Analysis >"Your Spam Specimen Has Been Processed." >Open a ticket for Hotmail<http://go.microsoft.com/fwlink/?LinkID=614866> ? > >From: mailop <[email protected]> On Behalf Of Andreas via mailop >Sent: Wednesday, October 11, 2023 2:13 AM >To: [email protected] >Subject: [EXTERNAL] [mailop] outlook.com 421 try again later S77719 > > >Hello all, > >since a few hours we have problems with sending to Microsoft. We get hundreds >of messages like in the subject with the reference to S77719. Also colleagues >from other companies in germany are seeing the same in their logs. All mails >that are blocked here are from Microsoft customers, but they are redirected >through our servers. > >Trying to unblock the IP e.g. via https://sender.office.com/ shows that the >IPs are not blocked. > >Anybody have any idea? > >Thanks a lot >Andreas _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
